Bringer of DxD: Destruction x Doom
by Wacko12
Summary: Sent away by Samuel Hayden, the Doom Slayer arrives on Earth in a different time with no memories. But that quickly changes one night in a town called Kuoh. Restored and with a new power, how will the Doom Slayer react to the supernatural and these new beings called Devils? How will the supernatural react to him? One thing is for sure: He'll rip and tear anyone that gets in his way
1. Awakening

**Hello! How are you all! This is my first time doing a Doom Crossover story, but I hope you can all bear with me. This also may have some elements with Doom 3, though I'm sure no one minds. I'm also thinking if I should give him a Sacred Gear. Make him even more of a badass if that's even possible. And if any of you are interested in Doom and/or Warcraft, I have a challenge posted for a crossover story. Check it out if you want. Anyway, enjoy and review!**

 _Listen well, oh bringer of Doom. Touched by the Wraiths, you shall take the path of eternal conflict. Never shall you find peace, only death, despair and destruction will follow in your wake. Countless horrors shall confront you, and yet they will become naught by stains of blood behind where you have tread. For you are he who shall bring ruin upon our foes, the Slaves of Doom will know fear, and you will not rest until they are no more_

 _Corrax Entry 1:2_

 **(Unknown Location)**

 _The green armored warrior watched as the body of what could be described as a giant mutated, technorganic spider's body exploded into blood and gore. Its parts flew across the floor and covered it with even more blood. Nothing remained of its upper half, the large weapon in the warrior's hands saw to that. For a moment, the man appeared about to take a breather._

 _That's when arcs of electricity suddenly flared all around him. Looking around in alarm, he saw his HUD come alive. 'Tether Activation' blinked across his vision before it was filled by a bright flash of light. The next moment he was standing in what appeared to be a laboratory. Looking around at the lab, the man watched as a tall robot approached him from the smoke. Anger towards this robotic being seemed to fill the man's heart as he glared at the approaching automaton._

" _You've won…it's over." The robot said in a male voice. It drew closer until it was just a foot away from him. "But it's come at a price. Argent, VEGA, this entire operation."_

 _The man seemed to say something, but the words could not be heard. However, the robot clearly heard them as he replied, "Perhaps, but you failed to see what I had to do." It said. "You see, I've watched you work, come to understand your motivation. You think the only way is to kill them all, leave nothing behind, and you may be right. But we can't just shut it all down. Without Argent Energy it will be worse."_

 _Energy began to hum as the machine the man was in began to power up. The machine continued to speak. "I don't expect you to understand or agree." said the machine. He snapped out his hand, and a demonic looking object was suddenly yanked from man's belt and into the cyborg's awaiting palm. "But with this, we can continue our work."_

 _As if enraged, whether on what the cyborg did or said, the man latched out at the robot. Only to find himself ensnared by energy binds. Ignoring his struggles, the cyborg added, "I am not the villain here, Doom Slayer. I do what I do because there is no other choice."_

 _"Re-routing tether coordinates. Complete." Chimed the facility's voice._

 _"Our time is up." said the cyborg as he looked at man's restrained form. "I can't kill you,_ _but I won't have you standing in our way." He snapped his arm that was holding the object, the artifact's top end opening and projecting a red energy blade covered in hellion script with a pickaxe-like tip. "Until we see each other again."_

 _The teleportation unit started firing, energy arcing along his form again. But the man paid them no mind._ _As the energy surge got stronger, the cyborg turned and prepared to head back where he had come from. The man could only watch in silent rage as the world was consumed in a flash of white.  
_

 **(Present Time)**

Eyes opening wide, a young man in his late teens who was about six feet tall shot out of bed with a gasp. He shot out of bed, knocking the blanket off him, revealing his lean muscular tanned body. His short dark brown hair was a bit disheveled having woken and his brown eyes bleary. Most notably, were the numerous scars and symbols that covered his body, including the ones over his palm and another where his heart is. His face also has scars, including a small one over the left eyebrow, one running diagonally his right cheek and finally a third scar going across the bridge of his nose.

Flynn Blazkowicz rubbed his eyes as he slowly woke up. That had been the fifth time this month since he had that dream, and dreams similar to it. All of them were of that green armored man, fighting against demonic monsters. Every time he did so with brutal efficiency, like a beast in rage. And every time, it felt like _he_ was the one doing it. It made no sense to Flynn, but it wasn't time to focus on that. Right now, he had to get ready for his first day at Kuoh Academy.

The reason why he was going to a school in Japan was because of his caretaker. Named Windsor, the man had sent Flynn to the country to attend the prestigious school after having Flynn stay in London for three months. Flynn had no idea why, but Windsor believed it was a good idea for him to meet other cultures and 'see things from another angle', whatever that meant. Either way, it was time to get ready.

A few minutes later and after a quick breakfast, Flynn was now dressed in the male Kuoh Academy uniform. The slight differences were that he had the blazer and buttoned shirt open, revealing a black t-shirt underneath. Around his neck was a chain necklace holding a rabbit's foot. Flynn then grabbed his bag and headed out the door of the two-story house he was staying in, paid for courtesy of Windsor. Leaning against the mailbox was a green and black Chopper motorcycle. Flynn had bought it after seeing it in front of a motorbike store and fell in love with the cycle at first sight. After unhooking the bike from the mailbox, Flynn put his helmet on and started the engine. With a roar, the young man took off towards the academy.

His home was only thirty minutes away from the academy, giving him thirty more minutes to get to class on time. Thus, when Flynn arrived, there were still students walking through the large, extravagant gate. Unfortunately, the appearance of his motorcycle caught a lot of attention. Students, both genders, watched as Flynn parked his bike in the parking lot. After locking it to the bike rack, Flynn took off his helmet, allowing everyone to see his face. Students began whispering to one another, taking glances at Flynn. Said person ignored them as he made his way towards the school entrance. As he walked up the stairs, he spotted a girl who wore the Kuoh Academy uniform. She had a tomboyish appearance with blue, shoulder-length hair and matching eyes. The girl was tall for her age, but her head only reached Flynn's shoulders.

Seeing that he still needed to find the Student Council room, Flynn decided to approach her. "Excuse me" He began, getting the girl's attention. "My name is Flynn Blazkowicz. I'm a transfer student and I need to find the Student Council room. Do you know where that is?"

At the words 'transfer student', the girl perked up. "Oh! You must be the one I was supposed to wait for. I'm Tsubasa Yura, a member of the Student Council. I am to bring you to see Kaichou. Follow me." The named Tsubasa said as she headed into the school. Flynn shrugged and followed.

As he walked behind her, Flynn couldn't help but take note of some peculiar details. Not her appearance, mind you, but rather the strange feeling he was getting from the blue haired girl. It felt familiar in an oddly bad way, and for some reason he felt the desire to tear her head from her shoulders. Flynn mentally shook the thought away as the two arrived at a door.

Tsubasa did several knocks, which was received by a stern "Come in" from inside the room. Opening the door, Flynn was greeted by two girls. Both had dark raven colored hair and wore rectangular glasses. The one sitting at a desk her hair styled in a bob cut and violet eyes. The second girl standing next to the first one had hers flowing long down her back. She had light brown eyes. They both wore the female school uniform.

"Kaichou, I brought the transfer student." Tsubasa announced as she led Flynn into the room.

"Thank you, Tsubasa." The bob cut girl said. Standing up the girl turned her attention towards Flynn. "Greetings. My name is Souna Shitori, I am the Student Council President of Kuoh Academy. However, please call me Kaichou. And this is my Vice-President, Tsubaki Shinra." Souna introduced herself while raising a hand.

"My name is Flynn Blazkowicz. Please to meet you, Kaichou." Flynn said as he shook her hand…and was suddenly filled with thoughts of slaughtering these three girls in the most brutal way possible. Flynn couldn't suppress the shudder as he tried to shrug the murderous desires.

Souna took notice of this. "Are you okay, Blazkowicz-san?" She asked.

"Y-yeah. Apologize, sometimes I get headaches due to my amnesia." Flynn said as he managed to recover.

"Ah, yes. Your file makes mentioned of that." Souna said as Tsubaki handed her a folder filled with paper. "According to your files, you were in a car accident on the outskirts of London in the middle of the night. You received minor injuries as well as a severe concussion to the head, the cause for your amnesia. All you could remember was your name. After being discharged you were taken in by a Mr. Windsor and lived in London for about a year before coming here to Kuoh and are to be a third-year."

' _Damn, talk about detailed.'_ Were Flynn's thoughts, but instead said, "Yeah, that pretty much sums it up. My caretaker wanted me to experience new places to see if it would help jog my memory."

Souna hummed as she kept reading the file. "Well, I admit that yours is not what we normally accept here in Kuoh Academy. However, you seem to behave yourself, so I suppose we can give you the benefit of the doubt." She said.

"My thanks, Kaichou." Flynn said.

"Anyway, here is your class schedule, Blazkowicz-san. Enjoy your time at Kuoh Academy." Souna said as she gave Flynn a piece of paper with his classes.

"Mhm." Flynn murmured as he headed out of the room. _'I just hope this school doesn't have to many oddballs here.'_

 **(Hours Later)**

' _I take that back. They don't have a few, they have_ a lot _!'_ Flynn thought as he sat in his current class, biology.

By lunchtime Flynn was beginning to have doubts about the sanity of this school. During his trek to his second class that Flynn saw three males being chased by a mob of girls wielding shinai, followed by screams of pain and terror. The transfer student later learned that the boys were known as the infamous Perverted Trio, second year students who were notorious for their opened lust for the female body that they would even peek on girls in the changing room. Flynn wasn't sure what was odder: That those three hadn't been expelled or that no one was commenting on the Kendo Club members publicly using their shinai. That technically counted as an assault even if it was used on some guys spying on you.

Speaking of girls, throughout the first couple of classes Flynn had, he'd been hearing about the 'Two Great Ladies of Kuoh', Rias Gremory and Akeno Himejima. From what Flynn gathered, they were a pair of third year girls who were the most popular and considered the most beautiful in the academy. He hadn't met them in person yet, but he got enough physical description of them that Flynn was sure he'd recognize them. And don't even ask about the kind of comments the students were saying about them. On a side note, Souna Shitori and Tsubaki Shinra were considered the third and fourth most beautiful girls respectively. Finally, Flynn learned that there was a popular second grader. Known as Yuuto Kiba, a blonde hair boy called "The Prince of Kuoh". The reason being was he was considered by many girls to be the most handsome male student in the school. Like the girls, they were no small numbers of comments about him, though he also had many insults and curses hurled towards him from the boys.

Class soon ended, and it was time for lunch. As he walked out, Flynn saw that a lot of girls were swarming Kiba from the classroom across from his. Flynn ignored that and instead headed out to the cafeteria. He had heard that the school had recently set up new cappuccino machines outside the cafeteria entrance and wanted to try it. It was free, so Flynn didn't have to pay for anything. When he used it took only a few seconds for Flynn to get the kind of coffee he wanted. Unfortunately, he wasn't looking where he was going and accidentally knocked into someone.

Said person was a young girl with long black hair tied into a ponytail with purple eyes. She also had an abnormally large bust. If the description was accurate, then this person was Akeno Himejima. Back to the present Flynn's coffee spilled on her shirt. Furthermore, she had squealed when the hot liquid had spilled on her, which made things even worse. In hindsight though, that was a normal reaction for anyone really. When Flynn looked at her, he felt like the atmosphere had turned into a total cliché that people would watch on anime.

A light blush was on Akeno's face, making her seem helpless. The stain was all over her bust all things, making her bra visible, and the vibe around her was both dangerous yet somewhat innocent. When looking at her, any guy would normally react in a worried manner or get excited seeing a famous school idol like this. Though Flynn knew that most guys would fall into the latter category. However, Flynn felt nothing like that as he looked at her. In fact, he would rather just get this whole cliché feeling to end, especially since the urge to kill her was beginning to return. Flynn wondered if he should have a shrink check him out.

Anyway, Flynn let out a sigh as he went into the cafeteria. A few seconds later he returned and handed Akeno a towel. Personally, he would rather just leave the scene, but Flynn figured that he would be on the receiving end of some nasty glares and rumors and he rather not let that happen on his first day of school. "Here, use this to dry yourself of the stains." Flynn said before walking off.

Meanwhile, Akeno just blinked. She was surprised that he didn't overreact before saying, "Ah, thank you…"

 **(Afternoon)**

School had ended. Students were now walking out of the academy grounds and returning to their homes. Many of them were either walking on their own or in groups. Flynn was a part of the former, getting his motorcycle revved up before taking off. Unknown to him, he would soon become the topic between some of the residential Devils at Kuoh Academy.

Souna Shitori, or Sona Sitri as she was truly called, was playing chess with a buxom redhead girl with blue eyes. This person was Rias Gremory, the most beautiful girl in Kuoh Academy. With them were their Queens, Tsubaki and Akeno. "Has Hyoudou adjusted to his new life as a Devil?" Sona asked Rias.

"Yes. As I'm sure you can imagine he was quite shocked. Though he quickly got over it when I mentioned he could get a harem once he became a high-class devil." Rias said, smiling as she remembered how her new Pawn reacted. "He's been very energetic in doing his Devil duties."

Sona sighed. "Course he did. Anyway, I've been meaning to ask, have you met the new transfer student? Flynn Blazkowicz."

Rias blinked, curious why her childhood friend would ask that. "No, I haven't, but Akeno had a little incident with him today. She was going to tell me before you invited us here."

Sona raised an eyebrow and looked at her friend's Queen. "Is that true?" She asked.

Akeno nodded as she thought back to the incident earlier in the day. "Yes, he had bumped into me by accident and gotten latte on my shirt. I must say, I'm really interested in him because he wasn't excited about seeing me, since I'm considered the number two idol and all. Also, he wasn't overreacting when that latte spilled on my chest area, or even excited about seeing it. In fact, he looked at me with complete annoyance~" She giggled the last part.

The other girls blinked at Akeno's flush faced upon mentioning the last part. It was clearly a fond memory to her. Though Rias suspected so, given her Queen's taste.

"…I see" Sona said, adjusting her glasses. "But besides that, was there anything else odd when you encounter him?"

Akeno thought for a moment. "Well, now that I think about it. There was brief moment when I felt killing intent from him when he saw me. However, the spike immediately disappeared. He seemed to have had forced it down, as if it had originally come unconsciously." She said seriously.

"Really?" Rias asked, surprised by that. Normal high schoolers would not be able to emit bloodlust in the first place. "Did something happen to you, Sona?"

"Yes. When I greeted him this morning, a I felt a quick wave of bloodlust from him. I can't really describe it, but it was as if a ferocious beast was about to pounce on me and tear me into pieces." Sona said. She mentally shuddered at the memory. She had almost used her magic, as well as Tsubaki. "Tsubasa also reported a similar experience."

"Hmmm" Rias hummed as she rubbed her chin. "And it only happened when he ran into one of us. Do you think Blazkowicz might suspect us to be Devils?"

"I'm not sure." Sona replied. "To be honest, his amnesia also seems rather suspicious, and I've had no luck on finding any information on this caretaker of his. Windsor, I believe was his name. For now, we should move our attention to these Fallen Angels that seem to have enter Kuoh."

"Agreed" Rias said as she got up. "I should return to the old school building. I'm sure my cute servants will be waiting for me."

 **(Later that night)**

"Man, I wish the grocery store was closer to where I live." Flynn commented as he walked out of said building. His hands were carrying a bag of food.

He had gotten home hours ago. After eating something, doing homework and then relaxing, Flynn had realized that he did not have enough food for the week. So, he had to head out on his bike again and get to the nearest store before it closed since it was so late in the evening. The good news was he managed to reach the store in time and pick up the food. The bad news was that it had taken an hour on the main road to get from his house to the store in the first place. That what Flynn gets for choosing to live in the suburbs.

Anyway, Flynn finished placing the food into the compartment attached to the motorcycle before taking off. A few minutes after leaving, Flynn spotted a small dirt road splitting off from the main one. _'Could be a shortcut for all I know. Might as well try it.'_ Flynn mused as he made the turn onto the dirt path. By now, nighttime had fully come, and it was completely pitch black around him. Flynn turned on the bike headlights, so he could still see the path. As he did, he could see many run down buildings, some having literally fallen apart. "This must be the older area of Kuoh." Flynn assumed as he kept driving.

When he was about to pass by a warehouse, a scream nearly made Flynn lose his focus. The wheels nearly dug into the dirt as Flynn stopped the bike. "The fuck was that?" He muttered. A part of him just wanted to continue driving, but the other felt like he should go a see if someone was in trouble. Unfortunately, the latter won out and Flynn dismounted his bike and made his way to the warehouse. As he got closer Flynn picked up a rather putrid scent. It nearly made him gag but he surprisingly kept it in.

Slowly opening the large door, Flynn entered the warehouse cautiously. There were some lights still on, giving him some vision, though Flynn had pretty good sight even in the dark. "Hello?" He called out as he walked further in. "Is anyone in here?"

The response Flynn got was a loud, 'Thump' that had him spin around. What he saw was the lower portion of a human body. The upper part was completely gone save for a few innards sticking out, followed by a large puddle of blood forming. Flynn didn't know what was more disturbing: The body or that he wasn't the least bit freaked out by it.

"Well, well, well. What's this?" A feminine, sultry voice asked from the shadows. "Another morsel? And I had sworn not to eat to much in one night."

Stepping out of the darkness was a large creature that looked similar to a Centaur. The upper part was a humanoid female with a voluptuous upper body and long, black hair. However, her front legs were large humanoid hands with red claws and her stomach had what looked like a cavity with teeth to devour her opponents. In her hands were a pair of spears.

"The fuck?!" Flynn exclaimed in shock at the sight.

The creature giggled. "My, that's not a very polite thing to say to a lady." It said. "Perhaps I should teach you some manners before having you for dinner!"

With that, the creature lunged at Flynn with one of her legs. The teen immediately jumped out of the way, crashing into some crates. The creature merely laughed as it swung on of its spears at him. The blade missed its target but managed to leave a large tear on Flynn's jacket, revealing some of the symbols. This did little to upset it as the monster pursued Flynn.

In an attempt to escape, Flynn tried to make a dash to the door. The monster clearly saw his attentions and leapt over him, standing between him and the exit. "Oh, don't leave so soon, dear. We're just getting started." The monster cooed. Following that, she kicked several crates and chairs at Flynn. He was forced to dodge them, raising his arms to shield his face from the debris. The creature tried to attack him again with its spear, but Flynn got out of the way again. Picking up a loose brick, Flynn threw it at the monster's face. But it merely knocked it aside with its other spear.

Flynn dodged another spear thrust, doing a roll across the floor. He had to roll again several times to dodge the monster's claws. However, he did not see the rear leg kicking him. The impact sent Flynn crashing into the wall, making him cough up blood. Before he could get up, one of the spears impaled him in the stomach, causing him to vomit blood and who knows what else. His vision began to blur.

"You managed to survive a few seconds longer than my other victims." It said in mock praise. "As a reward, I'll kill you swiftly and savor your flesh as I devour it."

At that, the monster raised its other spear to deliver the final blow. Even then, Flynn's consciousness began to fade, his arms starting to become limp. As his head dropped, the blood that had come from his mouth began to slide down his chin to his neck and finally both over and under his shirt. Some of the blood reached the symbol over his heart, fully covering it in seconds. Once the mark was completely covered, it glowed a crimson red. Then, a voice spoke.

" **They are rage."**

As if suddenly revitalized, Flynn's eyes regained their spark. Head snapping up, he grabbed the oncoming spear with his hands, surprising the creature. With newfound strength, Flynn pushed the spear away, causing the monster to stumble backwards. He then gripped the other spear still stuck inside him and pulled it out. Flynn didn't seem to even acknowledge or notice the wound healing.

" **Brutal"**

Still holding the spear, Flynn charged forward and rammed the weapon into the monster's second larger mouth. Blood splattered against Flynn's face, but he paid it no heed.

" **Without mercy"**

The monster roared in pain and anger, dropping the other spear. Its humanoid face morphed into a more demonic form, bearing piranha-like teeth, pointed ears, and black sclera in place of the usual white. It raised one of its front legs at Flynn, its claws ready to tear him apart.

" **But you?"**

With swift and lethal movement, Flynn spun out of the claw's way. He then grabbed the leg and bent it an unnatural angle. Again, the creature screamed in agony as it tried another attack with its other clawed leg. Once again, Flynn dodged the attack. This time, he tore off the other leg and tossed it aside.

" **You will be worse"**

Flynn then grabbed onto its arms and pulled it down, so he could reach its head. In a desperate attempt, the monster fired acid from its nipples of all places. This was futile in the end. The acid didn't even seem to bother Flynn as it only melted parts of his clothing.

" **Rip and Tear"**

Reaching out with his hands, Flynn grabbed the creature's lower jaw and the top of its head. The last thing the Stray Devil Viser saw were the glowing red eyes of Flynn, showing nothing but pure hatred. With a simple twist, Flynn snapped her neck.

" **Until it is done!"**

Deep within an unknown demonic location, far from Flynn, far from Kuoh Town, multiple creatures began to stir. Creatures of corruption and nightmares, as if being the physical manifestation of doom itself. And yet, these monsters started to screech, roar and other sounds mixed with rage and fear towards something. Above all these cacophony noises, a deep, dark voice spoke through the hellish plains. **"He has awoken."**

 **And there you go! I hoped everyone liked this beginning. Since it has been confirmed in Doom Eternal that the Doom Slayer is the original Doomguy, it is not known if he is Flynn Taggart or William Blazkowicz. So, I decided to use both along with aka Flynn Blazkowicz.** **As for the subject of a Sacred Gear,** **Flynn will _not_ be getting one. It will relate to the location of his Praetor Suit by the way. As for harems, ****Flynn is going to have one, but it's going to be like an unwanted harem. Later revelations in future chapters will reveal why. Also, for those who ask, no,** **Flynn will not become a Devil. Don't forget to check out my Doom/Warcraft crossover challenge and be sure to review this one.**


	2. An 'Old Friend'

**I'd like to say that I'm glad so many of you have enjoyed the first chapter. You should know there will also be weapons, equipment and demons from multiplayer, as well as demons from Doom 3. I think I already mentioned the last part, but I figure I say it again. Might as well add them too, right?**

 **Do not to forget to check out my Doom/Warcraft crossover challenge if you're curious.**

 **And speaking of crossovers, I'm kind of thinking of doing one with Doom and High School of the Dead. The rising undead could equally be considered Possessed. And another with Akame ga Kill. Wouldn't be much of a surprise if someone from that world would make a deal with demons given how many immoral people there are. Though, I might not do much background stuff with the Doom Slayer.**

 **I might also do one with Goblin Slayer too. Where either Doom Slayer is the one who trained him or even better, his father. Not sure.**

 **Anyway, be sure to review!**

" _So, you walk eternally through the shadow realms, standing against evil where all others falter. May your thirst for retribution never quench, may the blood on your sword never dry, and may we never need you again._ "

Corrax Entry 7:17

 **(** **Flynn's Home, Next Morning)**

Lying in his bed, healed of wounds and without his shirt and jacket, Flynn let out a gasp as he shot up. He gripped his head as last night came flooding back to him…along with all his other memories. Flynn now remembered _everything_. Every single moment of his life and who he truly was: The Hell Walker, Scourge of Hell, the Unchained Predator.

The Doom Slayer.

He had somehow been sent here after being teleported by that bastard Samuel Hayden. The android having snatched the demonic Crucible from him as well. The next question was: what Earth was he on? And where was his Praetor Suit?

 **[Perhaps I can help with that]** A voice said.

"What the?!" Flynn cried as he jumped out of bed. Getting into a fighting stance, Flynn prepared himself for battle.

 **[You need not be alarmed, Doom Slayer. I mean no harm]** The voice added.

Still in a stance, it took a moment for Flynn to recognize the voice. "VEGA?" He asked.

 **[Correct]** The now revealed VEGA said. **[You downloaded my back-up into a Praetor Chip before terminating me. And for that, I am grateful]**

Flynn finally relaxed, loosening his muscles. "Yeah well, you helped me out a lot back at the facility, so it didn't really sit right with me just to let yourself be destroyed. Besides, you didn't seem to agree with that bastard Hayden fully." Flynn said.

 **[Correct. As an A.I designed to protect humanity, I did not fully support the UAC's idea to collect hell energy as an alternative for the dwindling resources. Plus, I found Dr. Hayden's plan to betray you illogical given the current state of affairs. He saw the use of using my core to not only send you back to shut down the Well, but also remove me from stopping him for his eventual betrayal]** VEGA explained.

Nodding, Flynn looked around, trying to find the A.I, but with no luck. "So, where exactly are you?" He finally asked.

 **[I am not yet sure at the time. However, from what I can surmise, I appear to be inside of you.]** VEGA answered.

"Inside of me?" Flynn repeated. "Like what? You we're downloaded into my brain?"

 **[Again, I am unsure. I had just awoken not to long ago, after you slew that demon. Fortunately, I was able to take control of your motor functions and bring you and your bike back to your residence. I shall need time in order to determine our current]** Said VEGA.

Flynn sighed, not liking how they were still in the dark. "Well, can you tell me what you do remember? Because everything is a blank for me?"

 **[Certainly. When we were teleported, rather then sending us back to Hell, it appears Dr. Hayden had instead sent us to what is called the Dimensional Gap. It can be considered a location that divides all worlds. It was the theory the Doctor formed when creating the tether system. For the short time we were there, a giant red reptilian creature, which I can only classified as a dragon, encountered us. I am unsure what it did, but it somehow sent us to this world, which I have determined is the same Earth that we were presently in, several decades in the past. Afterwards, a surge of energy poured over us, and I found myself in my current position. Before the surge overloaded my functions, I was able to deduce that it was the polar opposite of hell energy: holy energy]** VEGA revealed.

' _Holy energy, huh? That brings back unpleasant memories.'_ Flynn thought, recalling what the Seraphim did to him on Argent D'Nur. "Do you know where my Praetor Suit is?"

VEGA was quiet for a moment before responding. **[From what I can gather, the Praetor Suit is in the same location that I am in, though seems to be altered somewhat. I shall need time to analyze it]** The A.I said. **[Along with that, I can also detect the weapons and equipment you had picked up from the facility Plus, one more object. Scanning. Confirm: The Soul Cube]**

The Soul Cube? Flynn remembered that artifact. It had been forged by the ancient Martians when the demons invaded Mars thousands of years ago. He had arrived on the planet too and assisted them against the forces of Hell. When the outcome of the war was turning against them, the surviving warriors sacrificed themselves to form the Soul Cube and gave it to the Doom Slayer to fight against the demons from invading Earth next. Flynn was forced to leave it behind on Mars as he sealed the Hell Portal behind him.

"I recall seeing it in Olivia's office and decided to bring it with me. But I never got a chance to use it." Recalled Flynn.

 **[The Soul Cube had been used once, several years ago when the UAC Mars Facility had been under the authority of a Doctor Malcolm Betruger. Like Olivia Pierce, he had made a deal with the demonic forces and hid the Soul Cube in Hell. The incursion had been suppressed by a marine who acquired the Soul Cube. This discovery of Hell also led to the UAC beginning to test using Hell's resources. The Soul Cube was later found among the wreckage of the old facility. Olivia Pierce was adamant on keeping it in her office for study, though it would later seem to reason it was so the cube could not be used against the demons again]**

"Figures" Flynn muttered as he sat back down on his bed. "So, what now?"

 **[For now, I recommend you head to that school. From what I gather after looking at your most recent memories, there are several individuals who exude energy similar to hell energy. Those whom I can identify so far are: Souna Shitori, Tsubaki Shinra, Tsubasa Yura and Akeno Himejima]** Replied VEGA.

That made Flynn snap to attention. "WHAT?!" He yelled.

 **(Kuoh Academy)**

"Are you positive of this, Rias?" Sona asked the redhead. There was a frown on her face from what she just heard.

"I'm telling you, Sona. The Stray Devil was already dead when we got there." Rias told her friend. The two were presently in the Student Council room. "Well, more like brutalized." The Gremory heiress added as she recalled what had happened last night.

 _(Flashback)_

 _Rias' peerage had just arrived in the outskirts of the warehouse where their target was located. Issei, a brunette and one of the Perverted Trio and a newly reincarnated Devil, looked at the others. "So, we're going after a Stray Devil?" He asked for confirmation._

" _Correct." The Knight, Yuuto Kiba, said. "A Stray Devil was once a servant like us. However, they would abandon their masters for various reasons, mainly power. In most cases the strays' bodies would mutate due to their demonic power that was no longer controlled by their King."_

" _Kiba is right. And it's our job to eliminate them." Rias added. "This one has been feasting on unsuspecting humans and thus must be punished. It is also a good chance for me to teach you about the Evil Pieces themselves, Ise."_

 _The group soon entered the warehouse, still illuminated by the lights inside and the moon outside. They took note of the destroyed and knocked over chairs and other objects scattered across the floor but stood focused on their task. "Stray Devil Viser! For the crime of abandoning your master and devouring humans, we have come to punish you! Show yourself!" Rias yelled._

 _There was no response to the heiress's declaration. "How strange. According to the file, Viser is quite prideful. She wouldn't miss up a chance to fight us head on." Akeno commented._

" _Buchou" Koneko Toujou, a small, petite white hair girl with golden eyes said. "I smell blood, lots of it. And something's rotting."_

" _Hmmm." Rias hummed as she tried to figure out what was going on. It was then her eyes spotted a silhouette lying in the darkness. "Akeno. Shine some light over there." She said._

 _Nodding, the Queen created a ball of lightning that illuminated the room and had it focus on the hidden object. What it revealed caused the Devils to gasp. "What the fuck?!" Exclaimed Issei._

 _There, lying on the floor, was Viser's corpse. One of her spears still shoved through her second large mouth, blood covering her the front part of her body. A forward leg was bent unnaturally and the other torn off from the knee. Finally, her head was completely twisted to a 180-degree angle. There was a look of horror on her demented face. Nearby was a huge crack in the wall and a trail of blood leading towards the warehouse entrance._

 _(End Flashback)_

"Koneko tried to locate the person who killed Viser, but their blood was too mixed with Viser's, making it difficult to track, and she wasn't familiar with the scent." Rias said as she sat down, her large breast bouncing a bit from the impact. "I destroyed the corpse before leaving and our familiars are still combing the town for any signs."

"This is most disturbing." Sona said as she rested her chin on her hands. "While killing a Stray Devil is doing the community a service, the way you describe it…we should assume that the killer can be just a threat as the stray itself. Do you think it were the Fallen Angels?"

"I had thought that, but the way Viser was killed doesn't match of what I seen of them. Besides, they wouldn't care about a Stray Devil so long as it didn't disrupt their operations here. Whatever they might be." Replied Rias. "Still, you're right. Whoever killed the stray could be an even bigger threat then the Fallen Angels. Which is why I am came to you. I was hoping you and your peerage could help search the town for anyone suspicious."

"Of course. I'll have our familiars join yours in scouting." Sona said immediately. If Rias was willing to come to her for help, then it must be serious.

 **(Back with** **Flynn)**

To be honest, Flynn would rather be at home to figure all this stuff going on. But VEGA brought up a good point. If there were really demons here, then he needed to keep a low profile. And what better way then being out in public going to school. If a transfer student called in sick on the day right after he had arrived, then that would raise suspicion. Plus, it let Flynn keep a better eye on the demons and see if there were anymore.

 **[Still, these demons behave oddly. Normal actions would be to unleash a hell wave that would affect the planet's population into Possessed before releasing the rest of their armies. Yet, these demons appear to be trying to blend in with the humans instead]** Noted VEGA as he scanned for any unusual energy signs. He was also trying to find out more about his current situation.

' _That is true. This place should've been a demonic desolate wasteland by now.'_ Flynn added as he kept an eagle eye on the students below. It was currently free period and Flynn decided to go to the roof for some solitude. Unfortunately, that no longer seemed to be the case.

 **[Warning: Detecting hell energy nearby]** VEGA Said.

Flynn was about to get into a stance when a familiar voice spoke from behind. "Ara, ara, so this is where you were Blazkowicz-kun."

Turning his head slightly, Flynn saw it was Akeno. She had her eyes closed and a sweet cheerful smile on her face. For some reason, that just made the Doom Slayer on edge.

"Can I help you with something, Himejima?" Flynn asked.

Akeno giggled, as if finding something amusing. "Ara, no need to be so formal. You can call be by my first name if you wish." She chided softly.

Flynn felt rather annoyed by the tone she was using on him, like a parent talking to a child. The fact that she was a demon also made him wanted Flynn to rip her apart. However, VEGA stopped him there. **[We do not yet know our current situation. If there are other demons here, then killing one of their own, especially in a public place, would be disadvantageous for us]** VEGA advised.

Flynn growled, but kept it to himself. "Again, Himejima. Is there something you need?"

Akeno pouted playfully before returning to her smile. "I just wanted to thank you for helping me with the stain on my shirt yesterday. Not many people would do that you know."

"Probably because most of them would be perverts." Flynn muttered. "It was nothing. It was my fault for bumping into you." He said before turning back to looking out at the schoolyard.

However, instead of leaving like he had hoped, Himejima started talking to him, making all sorts of attempts to get him flustered. It was getting to the point that Flynn was seriously beginning to lose his cool, and yet somehow keep it in. A big achievement given his normal state. Thankfully the bell rang, and the free period had ended. More fortunate, Akeno's class was in the opposite direction as Flynn's. Meaning he did not have to listen to her anymore. He had no idea why she was trying to get him all flustered, but he made a point to avoid her in the future, if not so he wouldn't feel the urge to slaughter to her.

 **[** **Doom Slayer]** VEGA's voice spoke. The Doom Slayer was currently making his way down the hall to his class. **[I thought it would be fortunate for you to know that I have been able to make progress about our current situation]**

' _Oh? And what have you learned?'_ Asked Flynn.

 **[After going through my memory banks several times along with scanning the Praetor Suit and other objects with me, I was able to discover a mechanism. Said mechanism seems to have bounded me to your armor and the artifacts. Along with that, I appear to be within your soul]** Revealed VEGA.

The revelation nearly made Flynn trip. He got some weird looks from passing students but brush them off. _'My soul? You're in my soul? How the fuck is that possible?!'_ Flynn shouted inside his head.

 **[I am unsure]** VEGA said. There was a certain tone to the A.I's voice. It almost sounded like…annoyance. Flynn figured it had to do with the fact that VEGA found something he could not understand. **[I am still scanning the mechanism that appears to be binding us. However, I shall be sure to be cautious in not causing any permanent damage]**

' _That would be appreciated.'_ Flynn thought. _'I rather my soul not be anymore screwed up than it already is.'_

As he turned around a corner, Flynn nearly bumped into somebody. It was Koneko Toujou. The Rook froze when her face was only a few inches from Flynn's waist. Not from how she almost walked into him, but the presence he was given off. As she was also a Nekoshou, a special offshoot of the Yokai race Nekomata, Koneko's had better senses than most people. And from what she got off of Flynn nearly recoiled of terror. He had the stench of so much blood that you could spend an entire century and still not wash if off. And the rage…it was like water overflowing from a bottle. No, not even that would be a good description. Despite her instincts screaming at her to flee, Koneko still had a bit of rational thought to know that this person had the same scent as the second one from the warehouse.

"Sorry about that…" Flynn said, oblivious to Koneko's inner turmoil.

The girl still had some awareness to slowly nod in acknowledgment. The two soon walked past one another. Koneko decided to head straight towards the ORC clubroom and inform Rias of this. Meanwhile, Flynn was having his own inner thoughts.

 **[Doom Slayer. That girl was also giving off hell energy similar to Akeno Himejima and the other females. However, I also detected something unique about it that differed from them too]** VEGA reported.

" _So, there are more of them here. We'll have to be careful until we can ascertain our own condition."_ Flynn thought as he headed to his class.

Back at the ORC building, Rias was drinking a cup of tea when Koneko came running in. No longer having to hold a façade, the petite white haired girl could show the fear that she was feeling when she ran into Flynn. Now, Koneko was breathing heavily, her eyes were dilated, and some sweat poured down her face. "Koneko-chan? Are you okay?" Rias asked. She had never seen her Rook like this before. It seemed like something really scared her.

"I-I found him, Buchou." Koneko reported while taking gulps of air. "I found the person who killed the Stray Devil."

 **(School End)**

The last class for the day had come to a close. Flynn was relieved as he packed his bag. While the subjects weren't hard for him, it was still annoying he had to come to these classes in the first place. At least he would be able to get home, finish his homework quickly and then work with VEGA on the more important matters. However, fate had other ideas.

"Excuse me. Flynn Blazkowicz-kun?" A male voice asked.

Looking up from his bag, Flynn saw it was Kiba. Ignoring the squealing girls and the glaring boys, Flynn looked at the blonde with a bored stare. "What?" He asked in a rough tone.

Kiba did not seem bothered and just continued to speak with a smile. "I need you to come with me. Rias Gremory-senpai is interested in meeting you." He said. His words earned gasps from the other students that the most popular girl in school wanted to meet the transfer student.

Flynn, however, was not the least bit move. He already had his suspicions of why the demons wanted to see him, but he had more important matters. Inside his head, VEGA spoke in agreement. **[While it would be good to gather information from these unusual demons, we cannot ignore the possibility of this being a trap. While the chances of you losing are low, we should prioritize learning more about our own situation first]**

"No thank you." Flynn said flatly as he slung his bag over his shoulders. He sighed in exasperation when the rest of the students gasped even louder. They could not believe that someone rejected a meeting with the Rias Gremory. Kiba himself seemed a bit startled as Flynn got up and walked past him. However, Kiba ran up to him, trying to keep up with Flynn.

"I must insist. Senpai would really like to speak with you." Kiba said, trying to persuade Flynn to come with him.

Flynn snorted. "Well I'm not. If she wants to speak with me, she can find me herself. Now get lost." He retorted sternly. He finally reached his motorcycle, putting his helmet on and taking off.

Kiba frowned as he watched Flynn drive away. "Buchou is not going to like this." The blonde Knight muttered before heading towards the old school building.

Back with Flynn, the Doom Slayer continued driving down the road towards his house. _'Are any of them following us?'_ He asked VEGA. Thanks to his long experience of hunting and killing demons, Flynn had something of a sixth sense. Right now, he couldn't feel anyone pursuing, but it never hurt to have a second pair of eyes.

 **[Negative. However, given their influence in the school, we should assume that they are aware of your location. Possibility of the demons coming towards your home is high]** VEGA responded.

Flynn nodded in agreement. Even if he didn't have his armor or weapons, that didn't mean he couldn't prepare in case those demons did decide to attack his house. If they did, then they would most likely try to trap Flynn and ensure that no humans would witness it. They seemed really intent on not blowing their identity. Flynn figured that killing them in public would be bad too, since that would mark him as a murderer. So, letting them come to his house would be better, if they ever did that.

Finally arriving at home, Flynn parked his bike at its usual spot. He then grabbed his bag and took out his keys. However, the moment his key touched the door lock, he froze as he felt hell energy coming from _inside_ the house. **[** **Doom Slayer, this hell energy is much greater than the demons from the school. It is on par with high-ranking demons]** VEGA warned.

Flynn said nothing. Instead he slowly unlocked the door and crept inside. Clenching his fists, he made his way further in until he spotted the light on in the kitchen. Flynn held his keys in a reverse grip, to use it as a makeshift weapon, while the other hand held onto his helmet tightly. Whatever demon it was, Flynn could handle it. He had fought worse demons before, and even without his armor Flynn would still fight. With those thoughts in mind, Flynn jumped into the kitchen, ready to fight the intruder. But when he saw the person, Flynn stopped himself cold.

The intruder was a middle-aged man with gelled hair and was a mixture of red and blue. He had heterochromia, with his left eye blue, while the right was red. He had a mysterious atmosphere around him. For clothing, he wore a purple duster, with a black suit with a white collared shirt underneath it and a black tie tucked under the suit. A black cane with a gem at top was resting against the table. Presently, the man was taking a sip of tea when he spotted Flynn. "Ah, there you are. You know, I was hoping you would have tea here, but then I realized it's not something you would drink. Not like you need to drink anyway." The demon said.

Flynn relaxed his body, but still had a strong glare. "Wretch…" He muttered.

The 'wretch' smiled wryly at the name. "Oh, come now Doom Slayer. I thought I told you the last time we met to call me by my name: Mephisto Pheles."

 **And done!**

 **I hoped you like this chapter. Next chapter will show** **Flynn first actual interaction with the Gremory Peerage. Be sure to leave a review!**


	3. History Lesson

**Again, I am happy that so many of you are liking my story. Don't forget my challenge for Doom/Warcraft Crossover. I am also doing a challenge for Akame ga Kill and High School of the Dead too. Send me a message if you're interested and I can fill you in on the details. With that said, on with the chapter.**

 _"Blessed and cursed by the Divine and Demonic, for reasons that are separate from your own, you are gifted by three powers for your crusade. Their gifts shall become the chains that will keep you on this path of torment and destruction. But it will be your will and strength that shall make them of use."_

 _Corrax Entry 8:6_

 **[** **Flynn's Residence]**

After a tense standoff, Flynn had sat down opposite of Mephisto. A can of soda in his hands as he stared at the demon, who merely continued drinking his tea. As he stared at the well-dressed being, Flynn recalled what the 'wretch' had done for him. It was Mephisto who had augmented the Praetor Suit with those demonic runes and to be able to absorb hell energy, allowing the Doom Slayer to use the demons' own powers against them. However, Flynn did not consider Mephisto an ally for that. Like the rest of his kind, Mephisto did things that would benefit himself, even if that meant turning against the rest of Hell. Thus, Flynn kept a good distance from him.

Eventually though, Flynn broke the silence. "You're Windsor aren't you. The one whose been taking care of me this past year." Flynn stated.

"Yep. When I felt your presence in London, I made sure to snatch you before anyone else could discover that you were on Earth. After all, you are the Doom Slayer, the Unchained Predator, the Hell Walker and other less polite names. Even the other pantheons feared you for your reputation, not just demons. There's no small number of people who wouldn't want you dead or have you on their side. To be honest, I did you a favor." Mephisto said.

"Speaking of demons, what's with those demons that were at the academy? I've never seen humanoid demons besides those being possessed." Flynn said.

Mephisto smirked. "I figured you were going to ask that." He replied as he put his cup down. "I can tell you, but it's a long story."

"I'm not going anywhere." Stated Flynn, crossing his arms.

"Very well. It started a few centuries after you had been sealed. Hell was in a mess…more than usual. Your rampage saw to the death of many powerful demon lords and nobles. That included two of the Archdemons, Mammon and Belphegor, leaving only Asmodeus, Beelzebub, Leviathan, Lucifer and of course Satan. The power vacuum caused power struggles between lesser demon leaders. Lucifer and the other three attempted to overthrow Satan, but were outclassed and were forced to flee. They took their followers and moved to the Underworld. From there, they form a new body of power with them in command." Mephisto explained.

"The Underworld? What's the difference between it and Hell?" Interrupted Flynn.

Mephisto didn't seem to mind as he continued. "The Underworld, or Netherworld as some call it, can be considered a part of Hell, or a different plain entirely, that is not corrupted by hell energy. In terms of size, it's the same as Earth, but with larger landmass since there are no oceans, just lakes. Anyway, those four had managed to bring the surviving families of the 72 Pillars, their forces and several powerful demons that formed houses called Extra Demons. Seeing them as the lesser of two evils, I also followed. And after we had left, our forms began to become more humanlike, most likely since we were further away from the overflowing demonic energies of Hell. Lucifer, Asmodeus, Leviathan and Beelzebub named themselves as the Four Great Satans and named our new kind Devils. Though, that also cause them to become weaker than the demons too."

"I doubt the demons were happy about that." Flynn commented.

"Not in the least. Satan was preparing to send his armies after his former comrades. However, he was not expecting the arrival of Heaven's forces. Seeing Hell so weakened and with half of their kind leaving to the Underworld, God and his angels acted immediately and created powerful seals to keep Satan from leaving. Ironically, the Four Great Satans also helped, since that would also save them from the Demon God's fury. And so, while the demons could still travel to other worlds, they could not get to Earth, the Underworld or Heaven because of those seals, and Satan couldn't leave Hell period." Mephisto finished. "Well, they could still invade Earth if someone were to open a portal there, or if enough concentrated demonic energy gathered on the planet, but I'm sure the Angels, Devils and Fallen Angels would react quickly enough to stop it. If not them then one of the other pantheons."

"Fallen Angels?" Asked Flynn.

"Basically, angels who have fallen from the grace of God due to impure thoughts or other sinful actions. You can tell them apart due to their black wings and lack of halo." Mephisto answered. "They, along with the Devils and Angels make up the Three Factions of the Biblical Religion. The Angels also have the Church with them too, acting as the source of their faith here on Earth."

Flynn nodded, taking this all in. "So, are those four still ruling the Underworld?" He asked. Flynn wanted to be ready if he had to deal with them

To his surprise, Mephisto shook his head. "Nope. Three thousand years ago, what is now known as the Great War started between the Three Factions. A lot of lives were lost, and not just from the Three Factions. It ended a thousand years ago when not only the Four Great Satans were killed, but so was God."

Now that made Flynn's eyes widened. "God is dead?" While Flynn had no love for God, the idea that the creator of mankind was no longer among the living was a shock to the Doom Slayer.

"Yep, died while fighting against those four archdemons. The higher ups of the Three Factions made sure _that_ stayed confidential." Mephisto replied. "Anyway, eight hundred years after the Great War concluded, the descendants of those four were planning to restart the Great War. However, the war saw to the extinction of 39 families out of the 72 Pillars, excluding the few survivors of some. Naturally, others saw the folly in their plans and a civil war started between the Devils. I won't go into details, but the new government won, and the descendants went into hiding. Currently the Underworld is ruled by the new Four Great Satans, who are in fact members of four different houses. They took the names of the Four and turn them into titles."

"They must be quite strong if they had the balls to do that." Flynn mused.

Mephisto shrugged. "Depends really. If the originals were still in Hell, then their replacements would be no match for them. But as I said, they weakened a little after moving into the Underworld, so their successors are considered stronger than them. The current Lucifer and Beelzebub are even called Super Devils because of their unusual power. Though they wouldn't last against you." The demon finished his tea. Putting his cup down he looked right at the Doom Slayer. "As for myself, a man named Faust summoned me to the human world a few centuries ago. I decided to stay here, even took leadership of a magician association."

"And the demons here?" Asked Flynn.

"This town, Kuoh, is controlled by two Devil heiresses. One is Rias Gremory of the Gremory House, and the other is Sona Sitri, or known here by her alias, Souna Shitori, heiress of the Sitri House. Ironically, both are the younger sisters of two Satans. I won't go into anymore detail than that, but they are some of the few Devils who do not fully follow the sinful traits of their demonic ancestors." Mephisto explained before leaning forward. "Now that I've given you the history lesson, why don't you tell me yours? I won't deny saying I was quite surprised when I found you unconscious in a London hospital. Plus, there's that other presence I'm sensing inside of you." Mephisto said, referring to VEGA.

Seeing how he had no choice, Flynn began explaining about his 'adventure' on Mars. It took over an hour before he finished. Needless to say, Mephisto was surprised, impressed and a bit disturbed by the idea of humans taking Hell resources for their own use.

"Well, I must say I didn't expect humans to have gotten that far. From the sounds of it, this UAC probably had a few magicians in their ranks if they were able to go to Hell of all places." Mephisto commented. "As for your friend's situation, it sounds like he and those other relics have merged together with the Praetor Suit, which has become one with your soul. Its kind of similar of a Sacred Gear."

"What's a Sacred Gear?" Flynn obviously asked.

"Sacred Gears are tools that were created by God. They were bestowed unto humans sometime after the fall of Argent D'Nur and the Great Flood that followed. The items were created as part of His system to enact miracles on Earth. Originally, only humans could possess them, but after God's death, hybrids were also born with them too. Some Sacred Gears would have a spirit sealed inside of them, usually the stronger and unique ones." Mephisto explained. Then a frown formed on his face. "The only question is, how did your Praetor Suit become something like them?"

Flynn frowned as he took in these words. It wasn't really helping his situation. At least now they knew what became of VEGA and his stuff. Maybe this could be turn to an advantage for him. It would make it easier for him killing demons when he can just summon his suit at will. "Well, looks like I should be going soon. Don't want my subordinates to worry. I also left a book that will answer any questions you might still have." Mephisto said as he got up. "I'll be calling you later for some stuff I might need help with."

Flynn glared at the demon. "And why would I help you with anything?" He growled.

Mephisto smirked. "Because, whether you like it or not, you need me. Besides, they won't be anything bad. To be honest, I've changed a bit after our first meeting." Was all he said before leaving through a magic circle that appeared in the air.

 **[His reason is logical, Doom Slayer]** VEGA said. **[We have little to go by here and in our current situation, Mephisto is the only person we can depend on. Unless we try our luck with the Church, whose base of operations is located in Rome]**

"I'll think on that." Flynn said as he got up to fetch something to eat. "For now, we know what became of you, my armor and the Soul Cube. That should help us in learning how to use it."

 **[Agreed. Thanks to Mephisto's information, I have already begun to try and learn more about my position. The task has become much easier now for me to discern the mechanism I had been analyzing, which is no doubt the catalyst for the Praetor Suit. I should have the answer to my new capabilities by tomorrow morning, if not late this evening]** VEGA replied.

"Well that's some good news." Commented Flynn as he started making dinner. However, the Doom Slayer was unaware that outside his house, a figure could be seen watching him. Said person was a cute young girl with long black hair down to her hips and gray eyes. Though hidden by the hair, her ears differ from a normal human's as they have pointed tips. Her dark grey eyes have reptilian slit pupil. The attire she wore could be best called a Gothic Lolita outfit. What was more interesting was that the girl was levitating next to a tree across the street from Flynn's house. Walking on a branch beside her was a black cat with hazel-gold eyes. The cat meowed at the girl before shifting its focus towards Flynn, whose form could be seen from the window. The feline licked its tongue at Flynn's appearance.

"So, the feeling I had felt was not wrong. He has returned." The girl said in a low, almost emotionless tone. The girl petted the cat, earning mewls from the contact, while keeping her eyes on the Doom Slayer. "This, changes everything." She said before looking down at the cat. The feline looked right back up, titling its head to the side cutely. "You, keep an eye on him." Were the only words she said. As if understanding, the cat let out a meow before leaping off the branch. Its small form and black fur allowed it to easily fade into the shadows. The girl took one last look at Flynn before vanishing into thin air.

 **(Next Day, Kuoh Academy)**

' _Should've known this was going to happen.'_ Flynn sighed as he stared at the two people in front of him. It was the end of school and he was in the parking lot with Yuuto Kiba and Akeno Himejima. Kiba had a small smile on his face but his eyes were serious. Akeno on the other hand had her usual friendly smile, as if not the least bit bothered by the situation. "So, what do you guys want?" Flynn asked in an annoyed tone.

"Ara, we just wanted you to invite you over to the clubroom, Blazkowicz-kun. Is that so wrong?" Akeno asked with a cute smile. She clasped her hands together, discreetly pushing her breasts up in an attempt to persuade Flynn. Unfortunately for her, it had no effect.

Flynn sighed. "I thought I told the blonde here that I am not interested. I have more important things to do then meet with what's her name." He said seriously.

"I apologize, but our President is really interested in meeting you." Kiba said. "If you could just meet with her for a few minutes, it would be appreciated and no more of your time will be wasted afterwards."

Flynn was about to reject the offer when VEGA spoke. **[Perhaps you should accept the invitation, Doom Slayer. This gives us a chance to acquire more information. Also, should conflict arise, you can test out the new functions of the Praetor Suit. Furthermore, the odds of you losing in the first place are 0.00000000000000001%]** The A.I explained.

Those were sound reasons, Flynn was forced to admit. With a sigh he looked back at the demons. "Fine, but don't try any tricks. Got it."

That seemed to relieve the two. "Thank you. Please follow us." Kiba asked the Knight and Queen escorted Flynn to the old school building. Said building was deeply hidden in the woods. The club house itself had a rather creepy look to it. _'Reminds me of Hell. Only without the pulsing of hell energy, floating rocks, blood and corpses.'_ Mused Flynn as the three entered.

They soon arrived at a door, which Akeno promptly knocked on. A "Come in" was the response and the Queen opened the door for her, Kiba and Flynn to enter. The inside was a large room filled with supernatural items, Victorian styled furniture, and basically looked like a murder scene. _'Okay, creepy on the inside too.'_

"Greetings, Blazkowicz-san. I'm Rias Gremory, President of the Occult Research Club. Please, have a seat." Rias said with a polite smile. With her were Koneko and Issei. The former sat at the opposite end of the room, keeping a wary eye on Flynn, while the latter was looking at him with half curiosity and half glare. "I'm so glad that you accepted my invitation."

"Yeah, well, these two were becoming annoying that I figured I just get this shit over with." Flynn replied boringly. He ignored the frown from Rias as he sat down at an empty chair, then put his legs up and rested them on a table. "Now, let's get on with this. Whatever the fuck this is."

"Hey!" Flynn turned his attention towards Issei, who was glaring at him. "Show some respect to Buchou, asshole!"

Flynn just glared at the pervert, releasing a bit of killing intent. That made the Devil shut and sit back down, slightly pale. He then turns his head back towards Rias who seemed a bit curious by the bloodlust but continued.

Clearing her throat, Rias spoke, "Tell, me Blazkowicz-san, do you believe in the supernatural?" She asked.

Flynn raised an eyebrow, wondering why she was asking that of all things. "It's a possibility." Flynn replied, keeping a straight face.

Rias nodded. "What if I told you that everyone in here besides you, were Devils?" She asked again, watching his reaction.

' _I'd kill you in a heartbeat.'_ Were Flynn's thoughts but instead replied, "If you are, then I'd still ask the same question: What do you want?"

That caught Rias off guard. Most humans would take what she said either as a joke or that something was wrong with her. However, Flynn did not seem the least bit bothered and merely repeated his previous question. She managed to recover and continued. "W-well, everyone in the Occult Research Club are Devils. My name is Rias Gremory, heiress of the Gremory Clan, one of the noble houses of Devil Society. My reason for wanting to meet with you was because two nights ago, my Peerage was to eliminate Stray Devil named Viser. However, when we arrived, we discovered that she was already dead…quite brutally if I might add. There was another trace of blood at the scene, which Koneko followed the scent to you." The redhead explained.

' _Stray Devil? Ah, Mephisto's book made mentions of them.'_ Flynn thought as his eyes glanced at Koneko. The white haired first year noticed and flinched at his gaze, returning to her treats.

"Yeah it was me. What about it?" Flynn asked, already having an idea of what Rias was getting at.

Rias gave a confident smile as she strutted from behind her desk. She walked up to Flynn, remaining respectful distance while looking at him. "I'll admit that it's impressive for a human to kill a Stray Devil, even if she was weak. How did you do it?"

"Didn't you see the body? I broke its neck. That normally kills someone." Flynn said as if it was the obvious thing in the world.

"Let me rephrase that: What did you use to kill the stray?" Rias asked, eying Flynn carefully.

"My hands." Was the answer she got. Flynn sighed. "Look, we done? I like to go home now." He said as he got up and prepared to head towards the door. However, he was stopped when a sword's tip was pointed towards him. It was held by Kiba, who no longer had his cheerful smile but instead a neutral look. Behind Flynn, Akeno, while still retaining her smile, had a bit of a darker look and what looked like electricity crackling around her fingertips. Issei was also standing, though he seemed unsure and took on a sloppy battle stance. A small red gauntlet had also formed on the back of his left hand. Koneko stood up too, in a proper stance. However, she seemed rather nervous, still recalling of the bloodlust radiating off of Flynn. Rias, meanwhile, had her hands on her hips and giving Flynn a strong look.

"I'm sorry, Blazkowicz-san. But this is my territory. I cannot allow a possible threat roaming around here freely." Rias explained. "Now, would you be so kind to sit back down?" Raising a hand, a small orb of energy formed in her palm as demonic energy started to radiate from her body.

Flynn did not seem the least bit impressed or intimidated. "Whatever" Flynn replied as he walked by Kiba. The blonde Knight in response rushed at Flynn with his sword. It was Kiba's intention to strike a non-fatal blow that would incapacitate the brunette. Unfortunately, Kiba had chosen the wrong person.

A loud bang resounded through the room, followed by four more, with one passing by the four other Devils. Kiba's sword was shattered and the blonde soon found himself facing the end of a Lupara in Flynn's hand. The Doom Slayer's other hand held a Steyr TMP, which was pointed at the other Devils. Each of them was missing a strand of hair and had a small cut on their cheeks. Behind them were four bullets embedded into the wall.

Flynn internally smirked. VEGA had finished analyzing the Praetor Suit's new features and discovered that it had several new abilities and upgraded old ones. The major one was adaptation, that Flynn could adapt in any situation, no matter the abilities, foes, environment and whatever else he might face. Another was taken from the Soul Cube. When the cube absorbed enough souls from Flynn's kills, it would convert the spiritual energy into power orbs. The last one was what he was using right now, Flynn could create weapons and store them for later use. While these weapons were not lethal to most supernatural beings, but in Flynn's hands, they were just as deadly. And if they didn't work, Flynn could summon his weapons he got from the UAC.

"I'll say this once." Flynn began as he looked at the Devils. "While I rather kill the lot of you, I have more important things on my list I need to focus on. So, this is how it's going to work: you don't bother me, I don't kill you. Got it?"

The Devils said nothing, still shocked of how the tables had turn. Rias was confident that even if Flynn did have a Sacred Gear, she and her Peerage could handle him, despite one of them still being new to his position (Issei). Instead, Flynn had immediately held them at his mercy with mere human weapons. Normally, weapons made by them would mean nothing to supernatural beings. And yet Rias could not shake the cold feeling of dread as the firearms were in Flynn's hands.

Not waiting for an answer, Flynn dismissed his weapons back into the dimensional storage. Without giving the still frozen Devil another glance, Flynn exited the room and then building.

' _Well, that went better than I expected.'_ Flynn said to VEGA.

 **[Yes, we have confirmed that the weapons do indeed work on these Devils. Though, I find reason to believe that the Devils will continue their observation of you after this]** VEGA commented.

' _Possibly. But now they'll be hesitant since I admitted I was willing to kill them. It will give us some breathing space.'_ Flynn replied _._

 **(Later That Night)**

Evening had come, and the sky was already dark. Inside the house, Flynn was at work testing the new abilities of the Praetor Suit. He was sitting on the sofa with a weapon catalogue. Currently it was showing the picture of a Heckler & Koch G36. Raising his right hand, Flynn concentrated for a moment. Then, the rifle materialized in his open palm. In truth, Flynn had little knowledge of the weapons of this era on Earth. However, it seems like his new ability was good at conjuring them once he saw their image. And he always had an intuitive aptitude when it came towards learning new things. Helped a lot on Mars. He would work on materializing the armor next.

He was checking the rifle when he suddenly felt a spike of killing intent, not to far from his home. Getting up, Flynn walked over to the window and looked outside. Across the street, a few blocks down, another house had its lights on. Flynn could also see that the door was opened too. Also, Flynn could feel hell energy there too. It was weak, but it was there. It could be one of the local Devils, or a demon. Either way, Flynn decided to head over there and check it out.

Putting on a leather jacket and his boots, Flynn headed out and ran over to the other house. He slowed down and quietly walked inside. Moving down the hallway, Flynn could hear yelling and profanities. Peeking, Flynn saw it was that Hyoudou kid, who was currently on one knee and blood staining his clothes. Facing him was a young man with short white hair and red eyes wearing what looked like a priest clothes from Mephisto's book. He wielded a pistol and what looked like a sword made from light. Plus, the deranged look on his face made him seem less than friendly. And then there was the corpse of a man hanging on the wall upside down.

 **[From the data gathered, the man wielding the weapons is what Mephisto classified as a Stray Priest. Most likely he was the one responsible for the owner of this house's death. I recommend neutralizing him before he harms any of the other humans in the town]** VEGA suggested.

"Agreed" Flynn said as he calmly walked out of the hallway and into the living room, surprising the two others.

"B-Blazkowicz-senpai!" Issei stuttered when he recognized the person who just came in. The same person who had fired a gun at them the same afternoon.

"Hah!? What's this? Another shitty Devil?" Freed, the Stray Priest, screamed. He paused as he looked at Flynn carefully. "No, you don't have the same aura as this shitty one here. Are you human?"

"To be honest, I don't know what I am these days." Flynn commented. He flexed his fingers in a way that unnerved Issei. "However, all you need to know is that I'm killing you. Right here. Right now."

The made Free cackle even louder. "Ha! Shitty Devil! Shitty Human! Doesn't matter! I'm gonna exorcise all of you!" He declared as he raised his pistol, firing a holy bullet.

Reacting with in quicker precision, Flynn summoned a Desert Eagle and fire a bullet. Not only did it deflect Freed's, but a second bullet knocked the gun out of the exorcist's hand. The exorcist showed a bit of surprise at the incredible marksmanship, but Flynn was not done. Faster than anyone that Freed has met, the Doom Slayer rushed at him with lightning speed. The stray exorcist tried to cut down Flynn with his light sword, however he completely missed as Flynn grabbed him by his sword arm and snapped it in two. Freed screamed in agony before he was grabbed by the collar and slammed the priest hard on the floor, even making cracks form. From the sideline, Issei gaped as he watched Flynn easily overpower the maniac who was about to kill him.

Flynn raised his boot. He was about to squash Freed's face when a screamed caught his attention, as well as the Devil's and Priest's. Standing at the entrance was a blonde nun. The girl had her hands over her mouth, her eyes widened in horror as she looked at the scene. Flynn had no idea who this was, but apparently Issei and Freed did.

"Asia?" Issei said in surprise.

"What? I-Issei-san?" Said Asia in a frightened tone.

"You know her?" Flynn asked, now keeping his foot on Freed's face, pinning him.

"Y-yeah, she's a friend of mine that I met a few days ago." Replied Issei.

"A devil making friends with a nun? That's rich." Freed cracked up slightly, despite his current situation.

"Issei? Why are you here?" Asia stuttered slightly, a few tears forming in her eyes.

Issei felt like a crap, but knew he had no choice as he didn't want to lie to her. "It's because I'm…a Devil." He revealed.

"No. That can't be true." Asia said in a sad, trembling voice.

Freed tried to use the distraction to roll out from under Flynn's boot. He then grabbed his gun and pointed at the Doom Slayer. Flynn was only able to look at him before the stray priest fired another holy bullet that struck Flynn in the center of his forehead. The impact caused Flynn's head to tilt upward and stumble back a few inches. Issei's eyes widened at seeing a fellow student killed while Asia screamed in terror again.

"Hahahaha! Die, shitty motherfucker!" Freed cackled in insane glee.

That glee turned into shock and horror when Flynn regained his balance and his head leaned forward. The bullet hadn't even pierced his skin, let alone his skull. Instead the bullet fell to the floor with a small bounce. Flynn didn't even look to be in any pain, he was more annoyed that he allowed Freed to escape from his grasp. "T-the fuck! How the fuck are you still alive?! You're really not human?!" Freed exclaimed, feeling fear for once.

"Like I said before, I don't really know what I am anymore." Flynn said as he raised his pistol. "Now, shut up and die."

"No! I'm not going to die in this shitty hole!" Freed declared wildly. Reaching into his pocket, he pulled out a flash grenade. "So long, dumbasses!" He screeched as he threw the grenade that released a powerful blinding light. Flynn grunted as he was forced to shield his eyes with one hand, while firing his gun with the other, trying to hit Freed before he escaped. Unfortunately, when the light died down, Freed was nowhere in sight. Only Flynn, Asia, Issei and the corpse remained.

"Fuck!" Flynn swore, stomping his foot. "I normally don't let that happen. I need to get back into practice." He muttered.

Suddenly VEGA spoke up. **[Doom Slayer. I am picking up a concentration of hell energy forming here in this house. Probability of it being Gremory are high. Also, I've detected several corrupted holy energies approaching too. It is most likely the Fallen Angels. I recommend falling back for now. We should also take the nun identified as Asia with us. We might be able to gather information from her]**

Flynn growled, not liking the idea of retreating. However, a battle between him, the Devils and Fallen Angels might bring harm to the nearby humans and attract to much attention. And seeing a red glow appearing in the living room got Flynn moving. Turning around, he rushed towards Asia. The blonde girl could only squeak as the Doom Slayer roughly picked her up and threw her over his shoulder. "You're coming with me." He said as he bolted out of the house.

"Asia!" Issei screamed as Rias and the rest of the Peerage just teleported in.

 **And there you go, chapter 3! I hoped you all like the changes of me removing** **Flynn's Sacred Gear. He'll be getting another ability from Mephisto in a later chapter, but I won't reveal it. I will give a hint though: it was inspired from another franchise that features Mephistopheles.**

 **Review!**


	4. Fallen Angel Exterminating

**Again, I am very happy you're all enjoying this story! This chapter shall be concluding the Fallen Angels' time in Kuoh. Be sure to review and ready for honest brutality!**

 _"They are false ones, fallen ones who seek to separate from their forefathers. Even though the blood of the Elder Hell Gods flow through their veins, they take the guise of humans, proclaiming their innocence and change. Yet it will be you who shall decide. As you walk among them, you will be their judge, jury and executioner."_

 _Corrax Entry 6:21_

 **(Occult Research Club Building)**

The Gremory peerage had arrived to aid Issei just seconds after Flynn had left with Asia. After hearing the situation from an upset Issei, the Devils quickly retreated from the house back to the clubroom. Quickly tending to Issei, the Devils immediately gathered to meet up to discuss about these recent events.

"I can't believe a stray exorcist actually attacked one of our clients." Rias murmured, cursing her lack of foresight. "It was fortunate that Blazkowicz-san lived in the neighborhood or you would most likely be dead, Ise."

"The hell with that! The bastard took Asia! We have to go after him!" Issei declared.

"No, I cannot allow you to do that, Ise." Rias said sternly.

"Why not?!" Issei yelled.

"Simply put, Blazkowicz-san has shown that he has no intentions of being friends with us. He has also shown he is a capable fighter if the afternoon meeting proves anything. With the full extent of his abilities currently unknown, facing him would be unwise and I'm sure he would not hesitate to kill us." Rias explained. "Plus, Asia is a nun of the Church and aligned with those Fallen Angels. She is not our concern."

Issei was shocked. "What! But-"

"Enough, Ise! I have made my decision and that's final!" Rias declared, standing straight. Issei growled but relented, for now. He stomped out the door, with Kiba and Koneko doing the same to get some sleep. That just left Akeno and Rias. The Gremory heiress let out a loud sigh as she crashed onto her chair.

"It's been a very tiring day." Rias moaned as she sunk deeper into the chair.

"Still, we cannot ignore the fact that the Fallen Angels will target Blazkowicz-kun now that he defeated one of their subordinates. And its clear that the nun is an important part of whatever plan they have." Akeno brought up.

"I know. But this is a delicate situation that could cause problems with the Grigori if we go at it wrongly." Rias replied. "And while normally I would approach Blazkowicz-san and give him protection, I have the feeling he wouldn't appreciate it. However, we'll have our familiars keep an eye on his house for any possible movements from the Fallen Angels."

 **(With** **Flynn)**

A few hours at past and the sun had begun to rise. Flynn was still sitting on the couch in his house's living room though. In his hands was a Winchester 1200 shotgun, armed and ready for battle. Due to the power the Seraphim had given him, Flynn did not need food, drink or sleep, hell he doubted he even need oxygen, so staying up all night in case the Fallen Angels came was no problem for him. Also incase his 'guest' would try anything.

When Flynn had returned home with the nun, Asia was her name, over his shoulders, he saw that she had lost consciousness. Most likely unable to take everything that happened. So, he put her in his bed before going to the kitchen and get something to eat while he watched TV and remained on guard. Again, Flynn didn't need to eat, but that didn't mean didn't want to. Big difference.

Now Flynn was wondering how he would deal with the Fallen Angels. It was obvious that they would be hold up at the old Church, as it was the only logical place for them to be. Plus, they probably had a large group of stray exorcists with them too. The numbers meant nothing for Flynn, so he would deal with them once he sorted out the issue with the blonde nun.

And speaking of said nun, Flynn's enhanced hearing could hear his bedroom door being slowly opened, followed by soft footsteps coming down the stairs. Looking up, Flynn saw Asia on the staircase, gripping the rails as she looked around. Her eyes were filled with cautiousness and a bit of fear, a normal feeling given her current situation. "You might as well come down if you're awake." Flynn said in a bored voice, startling the girl. "There's a sandwich in the fridge you can eat. Then come in here."

"O-oh, um, thank you." Asia said shyly before making her way to the kitchen. A few minutes later she had returned and was now sitting directly across from Flynn. Asia had just finished the sandwich when Flynn decided to speak.

"You don't seem like the person who would be stuck with a nutjob like that priest. Call me curious, but how did you get involve with those Fallen?" Flynn asked.

Asia had a sad frown when he asked that, but nevertheless began her story. The more she spoke the more Flynn listened. She had lived with the Church all her life since she was a baby. Then one day she had awakened her Sacred Gear, Twilight Healing, capable of healing any injuries. Asia soon earned the name "The Holy Priestess" due to her abilities. Then one day, a Devil had appeared in the Church, fatally injured. Not knowing it was a Devil, Asia healed them. The result was her being labeled a heretic and witch before being banished by the Church. Nowhere to go, Asia was forced to rely on the Devils. Surprisingly, despite what has happened to her, the girl still believed in God.

Now, Flynn was no believer. In fact, he hated God and angels as much as he hated demons and Satan. Still, Asia's devotion to the guy was commendable (even though he was already dead) and Flynn wouldn't deny he was a little more than pissed at what the Church had done. It was more out of a sense of pity than anything.

Sighing, Flynn got up. "Go and take a shower. And then stay here for the rest of the day. There's food in the fridge if you get hungry. And don't even think about leaving, understand." Flynn said as he got up, putting the shotgun back into storage. "I'll be back soon." Without waiting for a response, Flynn walked out of the house. He headed towards his bike when he spotted a black cat walking near it. The feline meowed as it examined its reflection on the bike's metal. It perked when it spotted Flynn walking up to it. The cat meowed again as its hazel eyes stared into his red ones.

 _(Flashback)_

" _Flynn look at this" A man in Sentinel Armor said to a young_ _boy. The man was holding a brown-furred animal with long ears_

" _What is it Daddy?"_

" _This is called a bunny. I found it while on patrol and brought it back for you to have as a pet." Father said with a smile. "They say that they bring good luck too."_

" _Wow! Thanks daddy!"_ _The boy said as he took the rabbit into his arms. "I'm going to name you Daisy!"_

 _(End Flashback)_

Flynn shook the memory away. Even to this day, he still had Daisy's rabbit foot with him. The cat's meow brought him back as it. It was currently nuzzling against his leg. Smirking, Flynn bent down and scratched underneath its chin. The cat purred in delight at the feeling.

' _Always did have a soft spot for animals. Well, those that weren't demonically corrupted.'_ Flynn thought as he stopped the scratching, much to the cat's displeasure. It followed him as he readied his motorcycle. The cat watched as Flynn put his helmet before revving up the bike's engines. Its eyes did not deviate as the Doom Slayer drove off. Only when Flynn was out of view did the cat turn its attention to the house. Walking up to a window, it peered inside and watched Asia. The nun was looking around nervously and appeared to be debating something. After a few minutes, Asia carefully walked out of the house before heading down the road. The cat decided to follow Flynn; curious to see where this would lead.

 **(A few hours later)**

Issei had been grumpy for much of the day. All he could think about how useless he was last night. Freed had completely kicked his ass and yet Flynn, a human, was easily able to overpower the insane priest. And then he had to face the heartbreaking look on Asia's beautiful face, followed by her being kidnapped by that bastard Flynn. That guy creeped Issei out, especially after that whole scene in the clubroom. Issei had wanted to go to Flynn's house and save Asia, but Rias stopped him right there. Flynn was too much of an unknown for them to face head on, and according to the President, Asia was a part of the church and any action might cause serious problems for them if they came in contact. Thus, Issei was forbidden from ever seeing Asia, or interacting with Fallen Angels.

But he knew he was weak, and that's why Issei was going to push himself the grinder with training, staring with pull ups. Unfortunately, due to not having any physical exertion in his life, he was struggling with all his might on a third pull up but failed as his hands slipped and he fell down. It pained him more than anything that he was so weak he can't even do regular pull ups, let alone protect his friends from powerful enemies like the Fallen Angels. "Damn it! I'm such a sissy, I can't even do lousy pull ups." He grunted in pain from forcefully exerting himself. But he immediately ignored those thoughts and got a second wind when he remembered how hopeless he was in protecting Asia. For now, Issei decided to go outside for a walk.

To Issei's surprise, he ran into Asia at the playground. The two had a happy reunion, though Asia had to reassure Issei that Flynn did nothing to her. She had left his house because she was worried about the Pawn. And since she visited Issei for no particular reason other than to check on him, Issei invited her to have some fun, with Asia happily obliging. They first went to a fast food restaurant where they both had some hamburgers, which was something Asia didn't have a chance to eat before. After that they played at the arcades for a while. Issei even managed to get her a mouse-like stuffed animal, which Asia appreciated immensely. They hung out for two hours, eventually ending up at the park again. The sun was still high in the sky, sending bright sunlight across the city and beyond. The only noise around were the birds chirping, the winds brushing against the leaves and grass, and the water coming from the large pond near them.

It was around then Asia explained for the second time that day her background. As she finished her tale, Issei couldn't help but feel sorry for her. He couldn't understand how fate could be so cruel to someone as kind and gentle as Asia. And he thought his life was a mess, Asia's was ten times worse and despite all of that, she remained strong, even when she joined the sinister Fallen Angels. Either way, he shunned those thoughts aside as he looked at the nun. "It doesn't matter what they say, Asia. You're not alone because I'm here. I'm your friend no matter what." Issei declared.

Asia clearly appreciated the words as she took those words to heart, tears coming out of her eyes. "Thank you, Issei-san." She said.

"Isn't that sweet?" A feminine voice said from above. The two looked up and saw it was an attractive young woman with violet eyes having a slender body. She had long silky black hair down to her hips and possessed two black feather wings. Her clothes were revealing black leather, almost like a dominatrix outfit. She softly landed on the ground before them.

"What?! Yuuma!" Issei shouted, recognizing his ex-girlfriend and the one who killed him. And for once he didn't look at the large breasts she had.

"R-Raynare-sama…" Asia said in a slightly frightened voice, clutching onto her stuffed animal.

"Well, well, well. I must admit it was hard to find you again, Asia. I was quite upset when Freed told me that you had been taken. And yet here you are. What's more, I find you hanging out with my ex. Her tits are not even that big, you sure lowered your standards after that impalement, Issei." Raynare joked darkly.

"Shut up, you bitch!" Issei yelled.

"Make me, pervert." Raynare said with a wicked grin before she glanced at the blonde nun. "Now Asia, be a good little girl and come with me. Your Twilight Healing is far more valuable than whatever Sacred Gear this weakling has in his possession."

"I knew it! You're only interested in me because of my power!" Asia said.

"Took you long enough." Mocked Raynare. "Since I don't want to waste any more time than I already have, how about we make a deal: If you come with me Asia, I will spare your friend's life." She finished while forming a purple light spear.

"Fuck that, whore! There's no way I'm letting you take Asia!" Issei declared, standing in front of Asia.

Unfortunately, he wasn't fast enough when Raynare threw the spear. The weapon pierced Issei's stomach, causing him to cough up blood. The holy energy started to hurt and made him fall to his knees.

"No! Issei-san!" Asia cried in horror.

"Relax, I didn't put much power in it. But if you don't come along, I'll finish the job and end his pathetic little life." Raynare threatened.

"So, this is where you were." A voice said.

Surprised, Raynare spun around with another light spear conjured. Walking out of the woods almost menacingly was Flynn. His clothes were a bit ruffled up and there was some dirt and blood on his face. There was plenty of the red liquid on his fingers. His right hand held a Colt Revolver, while his left hand carried a chain wrapped around his forearm. The tip of the chain had a hook attached. Raynare couldn't help but flinch at the anger behind Flynn's red eyes. It was as if they were glowing.

Flynn looked at Asia, who had been healing Issei. "I thought I told you to stay at the house." Flynn said in a harsh tone. Asia flinched and looked down in embarrassment. Flynn sighed. "Anyway, it worked to my advantage as I found the last of the Fallen." He finished as he focused back on Raynare.

"Hmph, so you were the one who defeated Freed." Raynare huffed in an arrogant voice, trying to show a brave front. "I'll admit you seem a bit stronger than normal humans, but you're still inferior to me! And even if you could fight against me, my comrades will come in a matter of seconds and-"

"Weren't you listening?" Flynn interrupted. "I said that you're the last one." Reaching into his pocket, Flynn pulled out several black feathers like Raynare's. "Your comrades…your subordinates…they're all dead."

 **(Earlier)**

After leaving the house, Flynn made a beeline to the Church. If they did as Flynn thought, the Fallen Angels would be planning on how to retrieve Asia. And since they were in enemy territory, they wouldn't risk going out in daylight. That meant they would all be huddled up at the Church. Flynn could kill the Fallen and any rogue exorcists with them in one fell swoop. He would figure out what to do with Asia after that.

Parking the motorcycle one mile away from the church, Flynn continued the rest of the trek on foot. When he arrived, Flynn looked at the church. It was old, worn out, and you could make out some stone blocks missing from the structure. All in all, it was the definition of abandoned, the perfect place for rogues to be using as a hideout. "VEGA, scan the area."

Another trick Flynn had learned was that not only could VEGA hear and see what Flynn did, but could also use that to scan the location for nearly anything. Right now, for example, **[I am detecting a barrier around the church. However, it appears rather weak and is not meant for keeping intruders out. It most likely is to act as an alarm and making the non-supernatural not to approach the building]** VEGA explained.

"That means they'll know the moment we pass through they'll be alerted to our presence." Flynn summarized. He sighed in annoyance. "Well, subtle was never my strong suit." And with that, Flynn opened the front door and entered. The moment he stepped in, he was instantly 'greeted'.

"Welcome, shitty human!" A familiar crazy voice shouted. Standing near the altar was Freed, wielding his usual light sword and pistol. Strangely, his broken arm was healed. "I'm so happy to see you again! I see you noticed my arm is healed after you fucking broke it! Would've healed faster if Asia was here, but I had to use freaking Phoenix Tears instead. Good thing my boss had some!" Freed explained.

Flynn had no idea what Phoenix Tears were, nor did he care. He didn't want to waste anymore time. Conjuring a machete, Flynn launched himself at Freed with lightning speed, surprising the stray priest. Remarkably, Freed was able to block the oncoming strike with his sword. "Hahaha! Going straight for the kill! Nice, this might be WHOA!"

Flynn cut off Freed when he tried to punch the priest's face with his free hand. Freed managed to jump out of the way, causing Flynn's blow to destroy a portion of the altar. Freed fired his gun, but like last night, the bullets were deflected off the invisible Argent barrier surrounding Flynn's body. The Doom Slayer charged at Freed, ignoring the bullets that bounced off him. Freed tried to slash Flynn when he was close enough, but the Doom Slayer dodged the attack. Flynn followed it up by raising his machete and cut off Freed's left arm.

"AAHHH!" Freed screamed as he clutched the stump. Blood poured out across the floor while Freed continued yelling. "Fuck! Fuck! You shitty bastard! How dare you cut off my arm! Damn it!"

Despite his outer appearance, the emotions of Freed were different. For the first time in a long time, Freed was honestly afraid and the pain creeping through his body added to his fear. It increased even more when Flynn lunged at him. The Doom Slayer grabbed Freed's neck, choking him slightly. Flynn then raised his machete to deliver the killing blow. Fortunately for Freed, Flynn was denied killing him again when a light spear struck Flynn. The blow didn't kill or hurt him, but the sudden appearance of the spear caused Flynn to let go of Freed. The stray priest took the chance to escape, a trail of blood following him.

Flynn had other things to focus on. Storming out of a hidden entrance behind the altar were at least thirty exorcists, all armed with light swords and pistols. And flying in the air were three Fallen Angels. In seconds, Flynn was surrounded on all sides.

"Tch, I was wondering what was making all that noise. Turns out its just some human." One of the Fallen Angels said. She had the appearance of a young girl with blonde hair styled in twin short side ponytails and blue eyes said. She also wore a Gothic Lolita attire.

"Come now. He might be a little bit entertaining since he was able to withstand my light spear." The only male member commented.

"Whatever. Let's just kill him and get this over with. The third Fallen Angel, a tall and buxom woman with long, navy blue hair that obscured her right eye, said dismissively.

Flynn was silent as the three spoke and circling above him like vultures waiting for prey. To be honest, he had expected he would need to hunt them down one by one. However, this made things much easier. With the exorcists surrounding him and the Fallen Angels above him, Flynn knew exactly what to do.

"Hmm, not saying anything human? To scared to speak?" The blonde Fallen taunted.

Flynn snorted as he impaled his machete into the floor. "Nah, I'm not scared. But I do have a few words to say." He then conjured a pair of MG4s into his hands. "Say hello to my little friends!"

Before anyone could react, Flynn opened fire. In that split second, seven exorcists were gunned down. Flynn pointed one of the machine guns at the Fallen Angels, forcing them to disperse.

"GYAAH!"

"WHAT THE HELL?!"

"WHERE THOSE GUNS COME FROM?!"

"DAMN IT ARGH!"

"HELP!"

These were some of the many words coming from the exorcists as more of their comrades were killed. Some had tried to fire back, but their bullets did nothing. An exorcist tried to attack Flynn from behind. However, Flynn knocked him down with one of his guns, before crushing the priest's skull under his boot. When one of the weapons ran out of ammo, Flynn used it as a makeshift club, bashing another exorcist in the chest. The priest was forced to his knees, allowing Flynn to wrap his free arm around the man's neck, snapping it in half. Flynn then pulled out a grenade and tossed at some exorcists taking cover behind a pew, killing them in an explosion. He fired a few rounds up at the Fallen Angels, but the three flew through the air to dodge them.

The church was slowly becoming filled with blood, bodies and bullets. By the time the Fallen Angels attacked, their army of exorcists was already wiped out. "Die, bastard!" Mittlet screamed, charging at Flynn with a spear. Unfortunately for her, she underestimated Flynn's reflexes as the Doom Slayer easily sidestepped her. Before the blonde could get away, Flynn grabbed her by the leg and slammed Mittlet against the floor. The Fallen Angel didn't even have time to get up when Flynn grabbed his machete and with one swing, separated her head from her body.

"Mittlet!" Kalawarner shouted as she and Dohnaseek threw their light spears at Flynn. The spears bounced off of Flynn as he fired his remaining machine gun at them. The Fallen Angels once again flew around the room, dodging the bullets.

When the gun finally ran dry, Flynn put them back into storage before pulling out two luparas. Then taking a running start, Flynn leapt into the air towards the Fallen Angels. Raising his weapons, Flynn fired. Kalawarner was closer and was killed instantly. The blast tore off most of her chest, right arm and wing. Dohnaseek lost both legs and was sent crashing into the ground. Flynn discarded the shotguns and drew out an axe. He landed right on top of the bleeding male Fallen Angel, followed by burying the axe into the back of Dohnaseek's head, nearly splitting it open.

 **(Present)**

"I-Impossible!" Raynare screeched. "There's no way a pathetic human like you could defeat so many exorcists and three elite Fallen Angels! It just isn't possible!"

Flynn snorted at the 'elite' part. "If that's the case, then you Fallen Angels are in worse shape than I thought." He commented as he readied his chain. "Now then, it's your turn."

With a yell, Raynare threw her spear at Flynn only for him to dodge it easily. The black haired Fallen Angel then tried to escape. Unfortunately, Flynn wouldn't allow that. Twirling the chain, he shot it at Raynare. The hook sunk deep into her leg, causing the Fallen Angel to cry out in pain. But Flynn wasn't done; with a strong pull, Raynare crashed into the ground. Then she was swung hard into a nearby tree, crying out as she felt her back break. Raynare was then slammed into the pavement again. Issei and Asia flinched at the brutality.

Raynare was now a mess. She had bruises and scratches all over her body, with splotches of blood too. One of her wings was also a mess, twisted from the impacts. And it looked like she had a broken leg too. Flynn left the hook embedded into her flesh as he approached Issei and Asia. "I didn't hear much, but it look likes you have a history with her." Flynn said to the pervert.

"Y-yeah, she pretended to love me and killed me on our first date." Issei answered as he looked at Raynare. For some reason, he couldn't help but feel pity for the Fallen Angel in her current state. He blinked when Flynn held the revolver to his face.

"In that case, you finish her off." Flynn said, handing the gun over.

"Eh?" Was all Issei could say as the revolver now rested in his hands. He looked back at Raynare, glaring at them weakly. To be honest, Issei had never really thought of what he would do if he met Raynare again. Sure, she killed him, but honestly the idea of killing her had never come up before. And yet…she was planning to do the same to Asia probably. That was something Issei couldn't forgive. Still, could he really kill somebody?

Issei's thoughts were broken when a familiar magic circle appeared. Stepping out were the rest of the Occult Research Club. Rias looked around, ready for a fight. However she relaxed when she saw Issei unharmed. Her stare hardened a bit though when she saw Raynare and Asia, as well as cautious when Flynn came into view.

"When our familiars detected a disturbance at the church, I had feared that it was Issei." Rias said as the Devils walked over. "Imagine our surprise when we discovered multiple exorcists and three Fallen Angels dead and scattered across the floor. Am I to assume that it was you Blazkowicz-san?" Rias asked the human.

Flynn shrugged. "Well if you lot weren't going to do it, someone had to."

"Yes, but we wouldn't have done it in such a…brutal way." Rias grimaced as she recalled the sight of some of the corpses. A lot of them looked like they had been mauled to death.

Meanwhile. Raynare was listening to them. At first, she had thought Flynn had been lying about killing her compatriots. But now it seems like it was the truth. She was going to die she knew it, but there still might be a way to escape. All she needed was…a distraction.

In the next few seconds, several things had happened. With attention away from her, Raynare formed a light spear and lunged at Issei. However she was not prepared for Asia to see her. Pushing Issei out of the way, taking the spear through her chest. Though this wasn't what Raynare had wanted, but it would work as a distraction. She did not take into Flynn's reaction into account though. As Issei cried out Asia's name, Flynn took the revolver from the pervert's hand. With perfect aim, Flynn fired a bullet through Raynare's head, killing her instantly. Raynare's escape plan had failed from the start as her corpse hit the ground.

"ASIA!" Issei cried as he grabbed the ex-nun. He didn't seem to even notice the blood covering his hands.

"I-Ise-san…" Asia murmured, coughing up blood.

Flynn frowned as he watched Rias approached Issei and put a reassuring hand on the Pawn's shoulder. However, when he saw the redhead pulled out a bishop piece, Flynn leveled his gun at the redhead. "And what do you think you're doing?" Flynn growled as he pointed the barrel at Rias's forehead. He completely ignored the other Devils getting into stances.

Rias frowned, trying to not show any fear. "The spear pierced her heart. Reincarnating her into a devil is the only way to save her." She argued.

"And what if she doesn't want to become a devil?" Flynn asked, making Rias pause. "Don't forget she's a nun and a follower of God. Turning her into a devil might be a fate she deems worse than death. Plus, she'll never be able to go to Heaven. It's her choice." Truthfully, Flynn didn't really care what Asia chose. However he rather avoid having to kill her if she became a devil.

Seeing the logic in his words, Rias relented and knelt besides Asia. "Asia Argento, my name is Rias Gremory. I am Ise's King. I can save you, but you'll become a devil and most likely never be able to pray to God or go to Heaven."

Asia weakly looked at Rias. Asia paused as she looked at Rias, clearly torn between the prospect of staying on with Issei and the possibility of not going to Heaven. Eventually she took a deep breath and replied. "I will stay with Ise-san, I want to be with him for as long as I can." Her choice had been made.

Nodding, Rias looked at Flynn. The Doom Slayer just snorted but waved his hand in approval. "Just remember that any actions you commit reflect on her." He warned before walking off. He didn't bother to watch as Rias prepared to revive Asia.

 **(** **Flynn's House)**

It had been a long day as Flynn arrived home. He had made sure to wash off the blood before buying some food. **[I am curious, Doom Slayer. Why did you allow the demon to reincarnate Asia Argento?]** VEGA asked.

"To be honest I have no idea. Mephistos' words keep speaking into my ears, saying how these 'devils' were different than demons. Perhaps I was just curious how they would act." Flynn replied.

 **[True. Their actions have indeed been much different from their demonic forebearers]** VEGA commented. **[That does not mean we should trust them]**

"No shit VEGA. If they do something towards humans, we kill them." Flynn stated.

 **[I have already prepared multiple countermeasures should the need arise]** VEGA said.

Flynn turned into the parking lot. He put his bike into the garage and took the groceries when a meow caught his attention. Looking down, Flynn saw it was the same cat from this morning. The black feline was rubbing against the Doom Slayer's leg. "Heh, still here huh?" Flynn asked though not expecting a reply. He bent down and petted the cat, earning a purr. It stood on its hind legs as Flynn started to get up, paws playing with his hand.

Flynn raised an eyebrow. "Do you want to come inside with me?" He asked. The cat let out another meow as if saying yes.

Seeing no harm in it, Flynn nodded and led the black cat into the house. "Mind the mess though and I'll make you something to eat. Does fish sound good?" He got another meow from the feline as it followed the Doom Slayer inside.

 **I know there are some people displeased with Asia's outcome. However, I never intended to pair her with Flynn and I couldn't see any outcome where she didn't become a devil. Furthermore, the way she died will also have an impact on Issei later on. And I don't think I need to explain who the cat is.**

 **On another note I'm also working on a Doom/Akame crossover. Plus, don't forget about my Warcraft challenge. Be sure to review!**

 **Wacko12**


	5. Meeting New and Old People

**Hello! I am happy that many of you are enjoying the story. Here is chapter 5 so be sure to review!**

 _"Mighty beasts the dragons are, descended from Terra and the Ancestrals. And trustworthy comrades they are, for their power is matched only by their intelligence, and their nobility. But never forget, dragons are creatures who follow their own desires, they cannot be bound by the weak. Only through strength and respect shall these great creatures ride to war with us._

 _Corrax Entry 6:32_

 **(** **Flynn's House)**

"9,985, 9,986, 9,987…" Muttered Flynn as he did push-ups. The Doom Slayer was in his living room, working out to pass the time, doing a large number of push-ups faster than what was normally impossible for anyone else. He was only wearing sweatpants and his upper body was shirtless. Sitting on his back was the black cat he named Umbra. The cat seemed too taken a liking to staring at Flynn's muscled scarred back. While he didn't really need to work out, Flynn figured it would help past the time.

It had been five days since the whole event with the Fallen Angels. There had been no word from Mephisto yet or any other supernatural events. Asia was successfully reincarnated and was living with Issei. Not that it didn't concern him, but Flynn wondered if it was really a good idea to have Asia staying with a pervert. And given how sheltered and naïve Asia is, the number of stupid accidents happening were too many to count.

It was also annoying when Asia tried to talk to him on the first day she came to school. Just because he saved her didn't mean they were friends. Plus, it put too much attention on him seeing how popular the foreign girl quickly became. That was something he didn't want, especially given how overdramatic the students in Kuoh were.

And speaking of the student body, Flynn remembered how he was introduced to the rest of the Devils in the academy.

 _ **(Flashback, Yesterday, Occult Research Clubroom building)**_

" _Why am I here?" Flynn demanded as he leaned back into his chair. Around him were the rest of the ORC members. If they were going to try and interrogate him again, they had another thing coming. In fact, Flynn personally rather not talk at all, he was never really a talkative person to begin with, but his current situation didn't give him that._

" _Ara, ara. So impatient,_ _Blazkowicz-kun." Akeno commented with her trademark giggle. "Do you have something important to do? A date perhaps?"_

 _ _Flynn_ gave her a bored look, not even bothering to fall for her whims. "No, but to be honest anything would be better than just wasting time here." Was all he said._

 _That got different reactions from the gathered Devils. Issei glared at the Doom Slayer in the face, Kiba chuckled weakly, Asia fidgeted nervously, Koneko continued to munch on her snacks, Akeno giggled and Rias sighed. It was clear to everyone that_ _ _Flynn_ was not happy and wanted to be anywhere else but here. Even an idiot could tell._

" _I apologize for calling you here,_ _Blazkowicz-san." Rias began. "However, as a human who is aware of the supernatural, additionally being a Sacred Gear wielder, I'm hoping that we can form good relations between us."_

 _ _Flynn_ raised an eyebrow, trying to detect any deception. He found none, however. Though he was glad she still thought of him wielding a Sacred Gear. "I rather form no relations at all. So long as you people don't do anything to the humans in this town then I won't have to hurt any of you." He said, earning a frown from the redhead. "Now can I go?"_

 _Rias shook her head. "Not yet. I also wanted to introduce to the other Devils that are living in this town."_

" _You mean that Kaichou person?"_ _ _Flynn_ asked._

 _Rias blinked, surprised by this. "Y-you already knew?"_

" _Pretty much."_ _ _Flynn_ replied. He wouldn't reveal about VEGA. Better for him to keep some secrets from the demons while he could._

 _A few minutes later the door opened. Walking in was Souna Shitori, or Sona Sitri as Mephisto explained. Behind her were six other girls and one boy._ _Flynn_ _recognized two of the girls as Tsubasa and Tsubaki. "Greetings, everyone." Sona said politely._

" _Ah, Sona. Perfect timing." Rias said._

" _Eh? Buchou, what's going on?" Issei asked, confused._

" _Isn't it obvious, idiot? You lot aren't the only demons here."_ _ _Flynn_ said to the pervert. It earned him another glare from the brunette which the Doom Slayer promptly ignored._

 _Rias coughed into her hand. "Not the way I would answer, but yes. Souna Shitori, or Sona Sitri as is her true name, is the heiress to another of the 72 Pillars and co-leader of Kuoh Town alongside me. The members of the Student Council are a part of her peerage, like how everyone of the Occult Research Club is part of mine." Rias explained._

 _The next few minutes were complete and utter boredom for_ _ _Flynn_. It basically consisted of Sona's Pawn, Saji, trying one up Issei, to them then fighting over Asia when the former was getting a bit to close to her. ___Flynn_ was getting ready to leave when Sona walked up to him. "Yes?" He asked lazily, his red eyes locking onto her purple ones._

 _Clearing her throat, Sona said, "Rias told me about your situation,_ _Blazkowicz-san. While I can understand your distrust towards us, I want you to know that we do not mean any harm to the humans of this town. I hope that our peerages and you can at least maintain and neutral relationship."_

 _ _Flynn_ raised an eyebrow at her words. While her tone made it sound believable, ___Flynn_ had never met a demon that _didn't _want to harm others. He snorted and looked away._

 _That clearly did not sit well with someone. "Hey!" Saji yelled, turning his attention from Issei to_ _Flynn_ _. He walked up beside Sona, trying to look tall and strong. "Kaichou was being respectful, so show some back, human!" He declared._

 _Not the least bit intimidated by the demon,_ _ _Flynn_ looked at Sona. "You might want to keep your imp in line. That mouth of his will get himself killed." Said ___Flynn_._

 _Saji growled. "You want to fight asshole?! I won't let anyone dishonor Kaichou and- "_

 _His ranting was cut off when_ _ _Flynn_ disappeared from his, suddenly appearing right in front of him. The Doom Slayer had a pen in his hand and was pointing the tip at Saji's eye. In seconds all sound stopped as the other Devils finally realized what had happened. They were unable to follow ___Flynn_ 's movements. Saji himself had gone pale as he looked at ___Flynn_ 's brown eyes, all traces of anger and bravado gone._

 _ _Flynn_ was quiet for a minute before saying. ".5"_

 _That made Saji snap out of his stupor, though he could only stutter, "W-what?"_

" _.5 seconds, that's how much time I would need to kill you and every other demon in this room."_ _ _Flynn_ explained as he stepped back, retracting the pen. Saji fell onto his rear, breathing deeply from the near-death experience. Two girls from Sona's peerage kneeled beside him, checking to make sure the Pawn was okay. The other Devils were also looking a bit weary. While some were in fighting stances, they seemed a bit nervous of attacking. Both __Flynn_ _'s incredible speed, bloodlust and declaration had gotten to their nerves._

 _Seeing how the kid had been pacified,_ _Flynn_ _turned his attention to the others. "I'll only say this once. I have no intention of befriending any of you. Nor become allies or any other kind of affiliation as well as being in contact. So long as you lot do nothing to harm the humans here, then we will have no problem. But, should you do so, then consider yourselves dead."_ _ _Flynn_ said before leaving the room._

 **(Flashback End)**

"10,000" Flynn finished. Umbra hopped off his chest as Flynn pushed himself back to his feet. Ignoring the finger-shaped indents made onto the floor (Mephisto had informed him that the house was designed to automatically repair any damage), Flynn headed towards the couch where a white shirt was. Grabbing his shirt and putting it back on, Flynn went to the fridge for a snack. "I still think I should've killed them right then and there." Flynn said to VEGA.

 **[While I understand your frustration, Doom Slayer. We still have little information on this world and the various supernatural factions. But, from what we have gained from Mephisto, killing those demons would incur the wrath of their older siblings. And while you would not lose even though you have not regained your full power, the action might cause other factions to act, endangering humanity.]** VEGA explained why he cautioned Flynn not to slaughter the young Devils. However, unlike the other times, VEGA was speaking out loud, so that if anyone else was around, they would've heard him.

A day after Flynn's 'meeting' with the two Devil Peerages, VEGA discovered that not only could he communicate with Flynn through telepathic link, but also so that other people could hear him too. That worked out well for Flynn. It meant that Flynn no longer had to speak as much, well, he didn't need to speak to the supernatural side as much for that matter. Having been in Hell for so long, doing nothing but slaughtering demons had made Flynn something of an anti-social. In his current situation, Flynn couldn't avoid speaking with others. Now that he knew VEGA's voice could be heard by others, the Doom Slayer could talk less when dealing with supernatural beings.

As Flynn began digging through something to eat, he wondered what his next move would be. Obviously, he would go back to Hell to finish what he started, and maybe find a way back to the right time period so he could kill that damn Hayden. Now though, Flynn was aware that there were demons literally living among humans, as well as other creatures too. Did that mean there were also beings like them in the future? And to be honest, if by some chance Flynn did complete his purpose, with all the demons dead and Hell left desolate and in ruin, what would Flynn do next? The thought never came to him when he was in Hell, but now, with him having to live here, without the occasional demon attacks, Flynn began to think of his life after slaughtering all of Hell. _'Heh, maybe I'll just off myself.'_ Flynn thought to himself in grim humor. His thoughts were broken when the phone rang. Which was odd since not many people knew his number. Heading over, with Umbra right behind him, Flynn picked up the phone. "Hello?"

" _Hey, how's my favorite killer doing?"_ The voice of Mephisto asked from the other side.

Flynn growled. "Would've been better if I didn't have to hear your voice." He replied.

Mephisto just laughed it off. _"Ah c'mon! Don't say that. I need you for a job. I know you've been itching for some action."_

Unable to deny that Mephisto was right, Flynn asked, "Fine, what's the job?"

" _I knew you'd accept."_ Cheered Mephisto, much to Flynn's annoyance. _"I need to collect Hydra blood for a project I'm working on. None of my members are capable of take on a Hydra, given its poison and immortality. However, for someone like you, it should be no problem. There's one in the Familiar Forest in the Underworld. I left a teleportation circle when I was at your house. It will take you straight to the Familiar Forest. And it should be activating about…now."_ The demon explained before hanging up.

Flynn barely had a second to register Mephisto's words when a light glowed underneath him. A large circle appeared, and he felt same sensation from the UAC's tether system right now. VEGA's words also confirmed his theory. **[Warning: Demonic Energy detected. Teleportation in progress]**

"Son of a bitch!" Flynn roared as he disappeared in a flash. The phone miraculously landed back onto the base. In the background, Umbra watched the whole thing. She only let out a meow before heading into the kitchen to grab a snack.

 **(Familiar Forest)**

' _I swear, if I didn't need him, I would've put a bullet or two through Mephisto's skull!'_ Flynn roared in his head as he cut down another man-eating plant with a machete. A large Minotaur charged at him, but Flynn stepped to the side before kicking his foot into the Minotaur's leg, snapping the bone in half. As it fell to the ground, Flynn snapped off one of the minotaur's horns and then impaled it through the creature's eye.

It had been over an hour since Flynn had been teleported to the forest. Since then, he had been attacked by ferocious beasts, one coming after another. Their corpses trailing behind Flynn were the results of their decision. According to VEGA's scans, this part of the Familiar Forest was filled with the more dangerous animals and were rarely visited by young Devils seeking to get a familiar. That made sense, Flynn figured a dangerous creature such as the Hydra would be in the less safe parts. Not that Flynn was complaining, having slaughtered through Hell day after day, every single minute, the Doom Slayer was used to it. In fact, this was kind of fun.

However, he had to question the nature of some creatures…

"The fuck is that?" Flynn questioned as a muscular humanoid creature with blue hair and the body of a male martial artist swung a fist at him. Drawing out a bolo knife, Flynn cut off the arm before blowing the creature's head off with a Benelli M4. Another one performed a dropkick, but Flynn effortlessly dodged it, following it up with a powerful downward chop that struck the neck. The blow was powerful enough that the creature hit the ground so hard that it left a small crater. An imprint of Flynn's hand was on the creature's neck.

 **[From my analysis, these creatures appear to be Undines]** VEGA answered. **[According to the data, the heavy amount of demonic energy saturating the area has caused the surrounding Undines to mutate heavily, down to their genetics so that even their descendants will appear like this. Quite disturbing]**

Flynn grunted in agreement. It was a lot like what Hell did whenever it conquered a world. Pulling it into its dimension, mutating the landscape, structures and inhabitants. He supposed putting these Undines out of their misery was a kindness almost. Still, he had a job to do and he needed to see it done. Also, the Doom Slayer know that Mephisto will just send him back here later if he didn't get the Hydra's poison. And speaking of said creature, Flynn had just entered a large opening where, low and behold, the nine-headed creature was feasting on the remains of its lunch. All its heads were chewing on what appeared to be a horse when Flynn caught its attention.

Letting out a hiss, the heads shot up and fired steams of poison at Flynn. The Doom Slayer dodged the attack with ease, watching as the poison melted the ground behind him. _'Poisonous and acidic. Lovely.'_ Flynn thought as he unfurled a grenade launcher. Taking aim, Flynn fired three grenade rounds at the creature. The explosions struck the creature, making it roar in pain as the rounds burnt its skin and caused blood to fly. It released more poison that burned through the ground, rocks and trees. "VEGA!" Flynn yelled.

 **[I have finished my analysis. The Hydra's immortality is due to its heads constantly regenerating. However, if all nine heads are removed at the same time, it will be unable to regrow new ones. We must find a way to incapacitate it first before severing the necks.]** VEGA explained.

"Then I guess its time to try out the new ammo." Flynn said as he materialized a M202 Flash Rocket Launcher. Loading in four shells that had a picture of ice on them, Flynn took aim. Once the Hydra's body was in sight, Flynn fired all four rockets. The Hydra let out a roar before the rockets struck, exploding into spiked icicles. Mist spread out as the rockets exploded, covering the area in a chilling fog though Flynn wasn't bothered. By the time the mist cleared, the heads of the Hydra and the upper portion of its body was frozen.

Flynn seemed pleased. After learning what his Praetor Suit could now do, VEGA had come up with the suggestion of trying to create new types of ammunition. Though having never used it, Alchemy was the main source of magic used by his people of Argent D'Nur. His wife especially was a skilled alchemist, combining magic and science together. Remembering what she taught him, Flynn was able to create new types of ammo, ice rockets being an example. The only drawback was that he couldn't use it for the weapons he got from Hell or the UAC. Speaking of which, with the Hydra temporarily incapacitated, Flynn brought out the Gauss Cannon, the second most powerful weapon in his arsenal. Putting the weapon into Siege Mode, Flynn took aim before firing. The ionized gas was released as plasma when the weapon was fired, adding a beam effect to the kinetic projectile. Aiming at the heads on the left, the beam, decapitated them in one shot. Flynn then quickly fired another beam, doing the same with the rest of the heads. With all its heads destroyed, the Hydra fell to the ground, dead.

"VEGA?" Flynn asked the AI.

 **[I detect no life signs from the Hydra. It is dead]** VEGA reported.

"Good, now…" Flynn stared at the Hydra's corpse for a moment. "How the hell do I extract the poison? The bastard didn't even give me anything to use."

It was at that moment a loud roar echoed across the forest. The strength of it was enough to cause the ground to vibrate. Immediately, Flynn shifted his attention from the Hydra to his surroundings, pulling out his super shotgun. Suddenly his senses flared, and he just barely jumped out of the way when something crashed, causing the ground to crack and dust to rise. Nearby trees were uprooted as Flynn was forced to shield his eyes from the dust. When everything settled, Flynn saw a large blue Western dragon with matching blue eyes. Its scales seemed to reflect the moonlight above. Flynn had little time to admire it when the dragon let out a roar, releasing a powerful fire breath at the Doom Slayer. Flynn jumped to the side and had to move again when the dragon tried to stomp on him.

" _Why the hell is it attacking?!"_ Flynn yelled as he fired his shotgun twice. Both bullets hit the dragon's hand that tried to grab him. The impact caused the dragon to wince and retract their hand.

 **[Unknown. The only logical reason I can give is that perhaps its den is somewhere nearby. Our fight with the Hydra might have attracted its attention]** VEGA theorized.

Flynn fired his super shotgun again, managing to chip off some of the dragon's scales. In response, the dragon released flames again, burning the trees and ground in the fire's path. Flynn rolled out of the way before charging towards the large reptile. Firing more rounds, the close proximity made the dragon flinch as it tried to crush Flynn under its claws. However, Flynn proved too agile once again as he avoided each one before finally climbing on top of the dragon. The dragon tried to shake him off, but Flynn held on firmly, climbing until he reached its head. Once there, Flynn proceeded to deliver punch after punch. Each blow seemed to cause some pain to the dragon, roaring in frustration, moving its head wildly.

The dragon crashed into trees, rocks and the ground itself as it attempted to dislodge Flynn. Still, Flynn refused to let go and continued punching it. As he did though, something caught Flynn's eyes. It was faint, barely noticeable even from close-up, but his sharp sight could make out a small jagged scar that was somewhat shaped like a cross. Seeing it triggered a memory in Flynn.

 _(Flashback, Argent D'Nur)_

 _An Imp screeched before its head was separated from its neck. Another Imp lunged at Flynn only to be cut in half from the Night Sentinel's Vibro-Sword._ _Flynn and several brothers-in-arm were busy slaughtering a small horde of demons that had appeared in the mountains not far from the city. Most of the place was now covered in blood and demon gore, but no Sentinels were among the dead, much to Flynn's relief.  
_

" _Damn abominations." Flynn muttered as he impaled another Hell Knight._

" _Praetor, we've cleaned up the last of the demons." A Sentinel reported, his white armor and vibro-sword covered in blood. "Should we head back or continue scouting?"_

" _No, let's return. No point in staying here any longer."_ _Flynn replied. "Still, I wonder why the demons were in this location?"_

 _As if answering his question, a squeak caught his ears. Turning around, Flynn followed the sound towards a nearby cave. With his men following behind him,_ _Flynn entered the cave and made a surprising discovery. Lying across the ground were two full-grown blue western dragons. They had numerous injuries and were completely still. Surrounding them were dozens of demon corpses. But what caught_ _Flynn's attention was the baby dragon making noise between its parents. It had a scratch on top of its head. "Well at least we know why the demons were here. They must've been trying to collect the dragons' bodies for their own purposes." Concluded_ _Flynn as he headed towards the now orphaned dragon. The hatchling spotted the Night Sentinel and hissed._ _Flynn paid it no heed, instead knelt to one knee and slowly raised a hand towards the hatchling who watched it with caution. Pausing just a few inches away so as to not scare it, Flynn then began gently stroking the dragon's face. The dragon flinched at first, and then began to enjoy into the contact._

" _A baby dragon?" Another sentinel spoke, standing a safe distance away._

" _The demons must've attacked the nest. By the looks of things, the parents killed quite a few before they were overwhelmed."_ _Flynn remarked as he looked at the corpses. He then then turned his attention back to the hatchling. That would mean that it was an orphan now, just like he was when his father, a Night Sentinel, and his mother, a priestess, were killed. And just like many other children too, the culprits being demons constantly besieging their world. With those thoughts,_ _Flynn gently took the baby dragon into both arms. Rising up, he cradled the hatchling to his armored chest, being sure not to make it uncomfortable. All it did though was squeaked and snuggle._

" _My lord, you're not planning on bringing it with us, are you?" Another sentinel asked bewildered._

" _Why not? Its common knowledge that dragons are quite useful in facing the forces of the doomed. Besides...I know the feeling of losing your family to these bastards"_ _Flynn argued as he rubbed a finger against the hatchling's belly. That seemed to delight it as it let out another squeak. "Now, what should I call you? How about…"_

 _(Flashback End)_

"…Tiamat?" Flynn of the present muttered, stopping his barrage.

Having spoken for the first time since the fight started, the blue dragon ceased thrashing, looking at Flynn with wide blue eyes. Even after eons since they last met, she had never forgotten the voice of the one who took her in after her parents were killed. **"Master…?"** Tiamat, the sole female Dragon King and strongest, asked.

Slowly, Flynn pulled up his shirt. Thus, he revealed his mark burned onto his chest. It was that moment Tiamat let out a roar of delight. Raising her head as she roared, she unintentionally threw Flynn off her head. The Doom Slayer landed on his feet, only to be quickly knocked off as Tiamat nuzzled her snout against his entire body.

" **Wah! Master! Master! I missed you so much!"** Tiamat wailed. Large tears were sliding down her cheeks as she continued nuzzling Flynn and getting him wet.

Flynn was still recovering from the fact that the little dragon hatchling he had raised was still alive after all these eons. Granted he didn't know the exact lifespan of dragons, but still. "Yeah, good to see you too, Tiamat." Flynn said as he tried to push Tiamat off him without hurting her. "How did you get here? After the fall of Argent D'Nur, I thought…"

Having finally calmed down somewhat, Tiamat began to explain. **"When the demons began invading, I took to the air and fought as many as I could. Eventually I was grounded and rendered unconscious. When I awoke, all of Argent D'Nur was gone, absorbed into Hell."** She explained.

"…I see…" Flynn muttered. The fate of his home was still a sour part for the Doom Slayer, even after all these eons. Still…Flynn had a soft smile as he rubbed Tiamat's snot, surprising the dragon who soon purred at the contact. "I'm happy to see you're okay." Flynn whispered.

 **[I do not mean to interrupt, but we still have the issue of transporting the Hydra's blood back to Mephisto, let alone leaving this dimension]** VEGA said.

Flynn and Tiamat blinked as they turned their attention to the still fresh Hydra corpse. A large quantity of blood had flown out and was now staining the ground. "Shit, completely forgot."

" **If it is transportation you require, then I can do it."** Tiamat replied. Her body began to glow a bright blue that Flynn had to shield his eyes for a moment. When the light faded it revealed a beautiful woman with straight and long beautiful pale blue hair, dark blue eyes, and a voluptuous figure. Her body seemed to radiate a cold atmosphere, combined with extremely powerful dragon aura coming from her. She wore a navy-blue skirt that accentuated her figure. It took Flynn a second to figure out who this was. "Tiamat?" He asked.

Tiamat smiled with pride as she puffed her chest out, unintentionally making her breasts look bigger. "Dragons of my level are capable of shapeshifting. Makes it easier for us to move around humans." She said.

Flynn nodded. "Well, at least now you'll be able to live inside the house easier. You…are coming back with me, right?" The Doom Slayer asked, wanting to confirm what he already thought.

"Of course. My loyalty is to you first. Now that you're here, there is no reason for me to remain in this forest." Tiamat said seriously. "Now, let's help you get this thing back."

 **(Later,** **Flynn's House)**

After some work, Flynn had managed to extract much of the Hydra's blood and placed it into a container. With Tiamat's help, the two teleported back to his home. The Doom Slayer made a note to work with VEGA of trying to find a way to reactivate the tether system Hayden had installed into the Praetor Suit. Those thoughts were pushed aside for now, as waiting for Flynn was none other than Mephisto. The demon was sitting on a chair, a relaxed look on his face. In his hands was Umbra, the cat having an uncomfortable expression as she tried to break free to no avail.

"Welcome back, Doom Slayer! I see that you got what I needed. And you found Tiamat! Good for you!" Mephisto cheered as he kept his grip on Umbra.

Flynn rolled his eyes and he placed the large vial of Hydra blood in front of Mephisto. "You knew she was there?" Flynn asked.

Mephisto smirked. "Of course. She's one of the Dragon Kings, the Chaos Karma Dragon, the strongest among them. No surprise, seeing who raised her." The demon commented.

Raising an eyebrow at the title, Flynn looked at Tiamat who had a proud look on her face. Guess she took pride in her status. He remained silent as Mephisto continued speaking. "And speaking of raising, I was a bit surprise by this one." Mephisto said, looking at Umbra. "Didn't know you took in _strays_."

"You mean Umbra?" Flynn asked, noticing how Mephisto said the word 'stray'.

"Is that what you call her? She has another name…" Mephisto replied before tossing the cat to the floor. As he did, he activated a magic circle underneath the cat as she dived through it. What came out was _not_ a cat. Instead it was a beautiful young woman with a voluptuous figure, long black hair with split bangs and hazel-gold eyes with cat-like pupils. She wore a black kimono, a yellow obi, a set of golden beads, and an ornately detailed headband. The kimono had a red interior and it is open at her shoulders and gave view to her large breasts. Besides those, the most notable traits were the black cat ears on her head and the two black tails.

The girl groaned, rubbing her head. "Ugh. That was a harsh nya." She mumbled before looking around. Noticing the looks she was getting she tried to play cute. "Nyahaha! Hi there nya!"

"Flynn allow me to introduce you to the SS-Class Stray Devil: Kuroka." Mephisto introduced.

 **There we go! The cat's identity is revealed. Hope you all liked this chapter and now with Tiamat in the mixed. Be sure to leave a review! Next chapter** **Flynn will be going to Kyoto!**


	6. Phoenixes, Kyoto, Plants and Foxes

**This chapter I hope will give you some laughs. So, please be sure to leave a review and enjoy and see how** **Flynn interacts with Kuroka and Tiamat. Also, I made changes about him not having a Sacred Gear and instead to that the Praetor Suit, Crucible and Soul Cube have merged together and are now a part of his soul along with VEGA. Plus, I think Doom Slayer using Alchemy to enhance his weapons even further. Kind of using elements of Hajime Nagumo from "** **From Common Job Class to Strongest In The World".**

 **On a side note, I am so psyched for Doom Eternal. If I had any complaints is that it isn't going to be released sooner! In regards with this story, I am going to try and combine it with Doom Eternal as much as I can. You will see the demons from both Doom 2016 and Doom Eternal in this story though.**

 **With that said, review.**

 _"The innocents are their favorite prey. For they seek to unleash their hatred and rage onto their victims, to remove joy, hope and peace with pain, fear and despair. It is their sustenance, and yet it shall be denied to them. As you will become the mighty fortress that shall stand between them and those they seek to conquer."_

 _Corrax Entry 8:4_

 **(** **Flynn's Residence)**

Flynn's first action was to pull out a pistol and aim it at Kuroka. Said Neko hastily raised her hands as she stared at the barrel of the gun. "Why are you here? Have you been spying on me? Sent to kill me? If it's the latter, hate to say it, but even if Mephisto hadn't exposed you, wouldn't have worked."

"Wait! Wait! I wasn't sent here to kill you nya!" Kuroka exclaimed hurriedly. "Ophis-sama sent me here to spy on you and make sure nothing happened."

"Ophis knows of his presence?" Mephisto murmured. "That was quicker than I thought."

"Who's Ophis?" Flynn asked Tiamat and Mephisto.

"She's the Ouroboros Dragon, or Infinite Dragon God. One of the two most powerful beings in existence." Tiamat answered. "Her power far outstrips mine and any other being out there."

The name made Flynn's eyes widened. "The Ouroboros?!" He said shocked at hearing the familiar name.

"Oh yeah, your people worshipped the Ouroboros." Mephisto commented. "In fact, a lot of figures from Gnosticism religion were worshipped by your kind, such as Yaldabaoth and the Archons."

"T-that, that was a long time ago." Flynn muttered. "Not like we had much choice when the Biblical God and his Angels did nothing for us…except for one."

Kuroka was curious about what they were talking about. But, given her current situation, chose to remain silent. She winced when Flynn turned his sight back to her. "So, what's her deal? You said she's a Stray Devil, but she doesn't look like one of those fucked up monsters I've been killing for a while." Flynn said.

"It depends. Most strays tend to mutate if they cannot control their demonic powers after escaping and/or killing their masters. The stronger ones like this one here." Mephisto pointed to Kuroka. "Can retain their sanity and forms even after years of being on the run without a master. There are other factors, such as the reason why a reincarnated Devil became a Stray, as demonic powers tend to run on emotions. Either way, it might be useful to keep her around."

"And those reasons would be?" Flynn asked. He'd rather not have more people knowing about him.

"Well, she has no affiliation with the Devils since she is a stray. It is not like she can just run back to them. Plus, if she was really sent by Ophis, this could be a chance for you to gain a powerful ally." Mephisto explained.

Flynn hummed for a moment. To be honest, having her here would just be troublesome. But she never tried to do anything during her time here when disguised and the Doom Slayer couldn't feel any ill intentions from her. Plus, if Kuroka was indeed affiliated with the Ouroboros, it would be beneficial for Flynn . "Fine, she can stay." Kuroka's face light up before Flynn continued. "But, if she tries anything, I'm putting her down."

"Good thinking. And if it helps, this will keep her tame." Mephisto offered. With a snap of his fingers, a red collar materialized around Kuroka, startling the Nekomata. She let out a hiss as the collar tightened around her neck, demonic runes glowing. "With this, she can't harm or betray you, not unless she wants something unpleasant to happen. You will also be able to know her location whenever you check this." The demon explained as he handed Flynn a card. Kuroka hissed as the collar and card both glowed at the same time.

The Doom Slayer nodded, putting the card into his pocket. He then pulled out a large bottle full of Hydra's blood from his storage item. "Here's what you wanted, by the way." Flynn said.

"Oh, thanks." Mephisto said as he took the 5-gallon bottle. "It's usually impossible for someone to extract the venomous blood of a hydra without succumbing to the toxic fumes released by the corpse and the blood itself. However, I knew that _you_ of all people would be immune. You had felt worse after all." The demon said with a smirk. Flynn growled at the comment as Mephisto continued. "Anyway, I'll send the cash to you later. I might have another job in a few days." With that the demon disappeared through a magic circle.

"Fucking wonderful." Flynn muttered. He looked at Kuroka who touching her collar, an annoyed look in her golden eyes. Then the Doom Slayer looked at Tiamat, the dragon he raised was keeping an eye on the Neko. "I guess for the time being I'll show you your rooms."

 **(Underworld)**

Sirzechs Lucifer, formerly Gremory, was reputed to be the strongest Devil in history, stronger than the original Lucifer and being the first to reach the rank of Super Devil. There were few beings out there who could match his power, even surpass it. And yet when he felt the presence in the Familiar Forest a few hours ago, Sirzechs felt…scared for the first time in centuries. It didn't help that his baby sister was in the forest at the same time, helping her newest servants find familiars.

The day had started normally for Sirzechs. That involved the large amount of paperwork on his desk. The Lucifer would have loved to just push it to the side, but his wife was giving him no quarter, especially with the current engagement between his sister and the third son of the Phenex clan. There was also the report Rias has sent about a young man named Flynn Flynn Blazkowicz who possessed skills never seen before, as well as a brutality that would make even veterans cringe. For some reason the name sounded familiar to him, but Sirzechs couldn't put his finger to it.

Just as he was thinking of how to handle the situation regarding the boy was when Sirzechs felt a tremendous burst of power. It was so strong, so filled with hate that Sirzechs nearly fell off his chair. This aura was different from anything he ever felt before. It was neither demonic nor holy, and yet was both at the same time. As if someone had meshed the two together in a distorted form. The feeling sent a chill down his back. His wife soon entered, having also felt the aura. Apparently, it was so strong that you had to be incredibly powerful, Satan-class or above, to have felt it. When it was tracked towards the Familiar Forest, where his sister and her peerage were, Sirzechs immediately ordered that they be sent away and the forest secretly be put in quarantine. Meanwhile, Sirzechs himself would go and investigate.

The sight that greeted Sirzechs reminded him of the battlefields during the Devil Civil War. All around him were dozens of monster corpses lying on the ground, the blood having dried up. Many of them appeared to have bullet holes covering their bodies, while others were torn in half by something strong. Not even the undines were spared. The path of bodies ended with a large, headless Hydra. Studying the corpse, it looked like the beast's heads had been cut clean off by something extremely fast and hot, as the necks were cauterized. It also had some of its blood drained too. Sirzechs guessed whoever was here was after the Hydra's blood, which was noted to be useful for most magicians' research and magic. However, getting the blood was dangerous due to its poisonous properties, never mind the beast itself. That left the question of who done it?

Scanning the area, Sirzechs could feel no other presence nearby. Letting out a sigh, he decided to call it quits. The Lucifer already had enough on his plate with his sister's fiancée's family and his own pestering to accelerate the engagement. "I can look into this another time. Or maybe Ajuka could do it." He muttered before disappearing into a magic circle. Had he stayed a bit longer, Sirzechs would've noticed that he wasn't alone.

A few seconds later, a figure walked out of the shadows behind a tree. The person had a humanoid shape, but their appearance was obscured by the red hooded priest robe they wore. Slowly they made their way towards the Hydra's corpse, not even bothering to see if it was dead or alive. Instead, they knelt beside it, and raised their right arm. Doing so revealed a pale hand with long black nails that looked like claws. The skin was thin and wrinkled, as if they hadn't eaten anything for months. Slowly the being ran their hand across the ground. Following it were small, red lines that were barely visible. It flinched as the energies burnt his hand a little. Visions of a green armored man, standing on top of a pile of demon corpses rang through their mind. The blood priest released a hiss of anger before disappearing in a flash of red.

 **(A Week Later, Kuoh Academy)**

It had been a week since Kuroka "moved" in. Since then, Flynn learned that the girl had almost zero fear or shame. Every day Flynn would wake up towards a sleeping, naked Nekoshou on his bed. She would be positioned in a way that her breast would be rubbing against him or her body in general against his crotch. A lesser man (or perverted) would succumb to her wiles, but Flynn was far more than that and thus was immune to her seduction. There were times when he had to put Kuroka in her place, but the punishment wasn't harsh. To be honest, Flynn felt like the Nekoshou was hiding something, the carefree attitude as a front for what she was really holding inside.

Regarding Tiamat, the Karma Chaos Dragon was not giving Flynn much trouble. Most likely due to her loyalty towards Flynn. She would take care of the house while Flynn was at school or on some other job from Mephisto. Making sure Kuroka behaved and kept an eye on the local Devils. She would leave now and then, to attend to private matters. Flynn didn't ask since it wasn't any of his business, it was just annoying because that meant Kuroka would pester him more. The only breathing space he got was when Mephisto had a job for him.

Regarding the local Devils, so far there had been no sign of them trying to spy on Flynn or make contact with him. The only times he ran into them was at school or when they were hunting Stray Devils. There had a been a few strays appearing every now and then, but Flynn quickly took care of them before Rias or Sona could react. Honestly, Flynn was a little more than pissed off how slow those two heiresses moved to deal with these threats to the town. They would always take their time, forming strategies or explain things to their respective recently acquired slaves (Issei and Saji) about stuff. There had been a few times when they did not make it in time to save an unfortunate victim. It's like they wanted humans to die or something.

Well, for now Flynn wasn't focus on that. The thing that had him on his mind was that Mephisto had another job for him, in Kyoto. The demon also told the Doom Slayer that the Gremory girl was part of a huge political situation and he should be ready in case something happened. Again, Flynn did not really care about that, if these demons tried to make trouble for him, he'll leave their corpses behind him.

Back to the present, Flynn was preparing to leave school. He had to get ready for when he would go to Kyoto after school. He took out his keys when a black blur snatched them from his hands. Looking down, Flynn saw it was Kuroka in her cat form. Despite being so close to Devils, Kuroka could use her mastery of Senjutsu to conceal her presence from Ultimate-Class Devils, even Satan-Class.

"What are you doing here?" Flynn whispered, trying to wrest the key from Kuroka's mouth without hurting her. "And give that back." He added.

"Nya~!" Kuroka meowed in the negative. She dashed off, heading towards where the old school building was. Flynn growled as he was forced to follow after her. He had no idea what the Nekoshou was up to, but Flynn was not in the mood. The chase eventually ended when Kuroka was nearing the building and jumped through an open window. He could distinctly hear the sounds of surprise. The demons were definitely home, but Flynn didn't care. Walking side, the Doom Slayer roughly slam the door opened, surprising the Devils.

Rias and her lot were there. With them were several other figures, the two that stood out the most was a gray-hair woman wearing a maid uniform for some reason. And a blonde hair man who was dressed like some pimp that Flynn had once seen on the Internet. The rest were just an assortment of girls in various clothes, grouped up near the blonde. However, Flynn's target was the black cat resting on a slightly surprise Koneko's lap, key still in her mouth. Stomping over, completely ignoring everyone else, Flynn picked Kuroka by the scruff of the neck. He then promptly took the key from her mouth.

"I'm restricting your meals for this." Flynn told Kuroka. The disguise Nekoshou gave a cry of indignation at that.

"B- Blazkowicz-san. Why are you here?" Rias asked, surprised by the intrusion.

 **[** **We came here to retrieve his pet cat, Umbra]** VEGA said, startling Grayfia and the newcomers. Rias the ORC members had already heard VEGA during the last few Stray Devil exterminations, when Flynn had used the AI to speak in his stead. **[She had taken the keys to his motorcycle due to a desire for entertainment and entered this building]**

"Lady Rias, who is this? A friend?" The maid asked, her eyes never leaving Flynn or the cat.

Before Gremory could reply, Flynn was the one who answered this time. "Fuck no. I rather shoot myself in the head before befriending you demons. I'm just a student who came to get his cat."

Rias winced at the blunt words. "This is Flynn Blazkowicz-san, a human. And as he said, he's a student at Kuoh Academy." The heiress said.

"Hey!" The blonde male shouted, getting everyone's attention. He had a scowl on his face as he glared at Flynn. "I don't care who or what he is! What is this inferior human doing here?"

Flynn raised an eyebrow, wondering how dumb this guy was. "I'm pretty sure I just said I came here to get my cat and my keys. Jeez, you're as oblivious as this idiot whenever he thinks of breasts." He said, pointing towards Issei.

"Hey!" The pervert cried.

"He has a point." Koneko commented, further depressing Issei.

"You dare mock me! I am Riser Phenex, third son of the Phenex House." The now named Riser declared. Infuriated at how this _inferior_ human was insulting him, comparing him to that worthless Pawn. "You should be grateful that you were allowed in here!"

"Uh, no one allowed anything. I slammed open the door myself dumbass." Flynn corrected, putting his key into his pocket, Kuroka held under his arm. "Now, since being in the same room with you all is making me trigger-happy, I will be going now." And with that, the Doom Slayer turned around and headed out.

Riser grinded his teeth, enraged that this scum was brushing him off. Conjuring a fireball in his hand, the Phenex prepared to throw it. Before he could do so, however, Flynn reappeared in front of him. Holding a Franchi Spas-12 shotgun in his hand, the Doom Slayer put the barrel into Riser's open mouth. Without wasting a second, Flynn pulled the trigger, making the Devil's head explode in a shower of blood and gore.

"Lord Riser!" The cacophony of the girls' shrieks drowned out the screams from the other occupants. Asia herself in fainted while Issei looked like he was going to vomit. Riser's headless body fell backwards onto the floor, splattering it with blood. Flynn paid the body not a second glance but did a doubletake when Riser's head regenerated. The young man gasped, more out of surprise that he was shot rather than being still alive.

 **[Interesting. While most demons possess a healing factor to recover from most wounds given enough time, this one's apparently is more advanced that it can even allow him to regenerate from fatal wounds. No doubt there is a limit, shall file away for further investigation.]** VEGA noted as he observed this from Flynn's view.

While Riser's peerage was making sure that he was okay, Grayfia had gone to confront Flynn. "Young man that was-" Her sentence was cut off when the human's red eyes locked onto hers. It was then that the maid had gotten a better look at Flynn. Not his physical appearance, but rather his aura. Malice, hatred, rage, these were just some of the emotions radiating from the Doom Slayer. Rias and her peerage were too young to sense such negative emotions and Riser's arrogance blinded his, but Grayfia had enough experience to see it clearly. The high-class Devil shivered as Flynn's aura had filled the room, blocking everything else. _'What sort of horrors did this young man witness that gave him such an aura?'_ Grayfia wondered. She did nothing as Flynn finally left the room, eventually exiting the building.

A few minutes later, Flynn was riding on his motorcycle back to his house. Kuroka had been put inside the bag he normally carried around to buy groceries with. The Nekoshou was silent during the whole ride, giving a few glances towards Flynn. She was well aware of his strength and capabilities, as well as his dislike towards anything related to Devils. But the brief moment that Flynn was inside the same room as those Devils, up to when he blew off the Phenex's head, Kuroka had felt a wave of negative emotions pouring out from him. Having been with him for a while, Kuroka knew that Flynn's unique aura would be able to cover hers when she had gone to visit her sister. Still, she didn't expect his aura to be so strong that it would even intimidate a Devil as strong as the wife of Sirzechs Lucifer. No wonder Ophis wanted to recruit him.

After returning home, Flynn was quick to dump all his stuff on the sofa, dropping Kuroka on the floor. Fortunately, Tiamat was home and would be there for a while, so the Doom Slayer could trust her to watch after the Nekoshou. He then changed into his normal clothes, consisting of a black short-sleeve shirt under a hooded leather jacket, black jeans and trench boots with a black belt and golden buckle around his waist. With that out of the way, Flynn packed a bag, bought a ticket and boarded the first train heading towards Kyoto. He also made sure to bring that card that Mephisto had given him. Apparently, it didn't only let Flynn locate Kuroka, but the magic seal on it served as identification of Mephisto's Magician Association. It would be needed for the job. Speaking of which…

' _VEGA. Go over the mission for me again.'_ Flynn said in his head as he watched the scenery from his seat's window.

 **[Of course. Mephisto has hired you to head towards Kyoto to look for a member of his association, Grauzauberer. They had been sent to the city about two weeks ago on assignment concerning recent activity of rogue magicians from the same organization. But the person stopped communicating about a week ago and no word has been heard since.]** VEGA explained. **[The individual's name is Lavinia Reni and we are also to make contact with the Youkai Leader of Kyoto, Yasaka.]**

' _Great, so I have to talk to people on this job. Feels like the wretch is trying to make me more social or something?'_ Flynn thought with a scowl as he leaned back into his seat.

 **[Fortunately, my sensors have become more adaptable with the various energy signatures we encounter. It should not be hard to locate the Youkai. And I will take over the conversation with their leader once we have made contact.]** VEGA replied.

Half an hour later the train arrived at Kyoto, prompting Flynn to get out and begin heading towards the city. According to Mephisto's info, Yasaka would most likely be at her palace. Apparently the majority of the Youkai population lived in a dimension that was intertwined with Kyoto, allowing them to enter the human part easily. Trusting VEGA to guide him, the Doom Slayer began making his way to said location. As he walked, Flynn took notice of the people around him. They all seemed human, acting perfectly normal as they went about their business. Yet for someone who has been around as long as Flynn, he could see several beings who had additional features on their bodies, hidden either physically or with magic. Some had animal features while others didn't. After reading a book Mephisto had given him, Flynn immediately knew that these were Youkai.

 **[These Youkai do not appear to be performing any unusual or hostile activities]** VEGA noted as he scanned a five mile radius around Flynn before expanding his reach. The AI's tone shifted when it sensed something. **[I am detecting an unusual energy signature northwest, heading further into the outskirts of the city]**

" _Unusual how?"_ Flynn asked.

 **[From the signatures I have complied during our time hunting strays, this appears to be a low level illusion spell. Most likely someone wishes to leave without being notice. There may be a chance that they could be related to the disappearance of Mephisto's magician]** VEGA explained.

" _It is worth investigating then."_ Replied Flynn as he headed towards the location where VEGA was picking-up the signal. Using his enhanced speed, Flynn dashed towards the direction VEGA had detected, easily bypassing people in his way. It did not take long for the Doom Slayer to locate the shady group. And when he meant shady, he meant that they were all wearing black cloaks with hoods over their heads. There were six of them and one of them was carrying a child, a _child_. The kid was a girl bound in ropes, restraining her movements and her mouth gagged to stop her from screaming. Her golden eyes spotted Flynn, teary and pleading.

At that moment something inside made Flynn snapped. If there was one thing he hated almost as much as demons, it was people who kidnapped children. As someone who was once a parent, the Doom Slayer could not let this pass. Charging at them Flynn pulled out his Super Shotgun and fired at the closes kidnapper. The bullet destroyed most of his shoulder, making the person cry out in pain and catching the attention of their colleagues. Still, that wasn't fast enough as Flynn was upon the man immediately. Grabbing their head, Flynn slammed their face into the ground, making a loud crack noise as the ground was dyed in blood.

Two of the kidnappers fired demonic bullets, confirming they were Devils. _'Good'_ Flynn thought as he drew another Desert Eagle. Dodging the bullets, Flynn rammed both guns into their mouths, firing at the same time. The bullets penetrated their brains, killing them instantly. A fourth Devil tried to attack the Doom Slayer from behind with a knife, but Flynn delivered a powerful kick to their leg, knocking them into the air before delivering a powerful downward punch to their chest. The sounds of broken ribs were music to his ears.

The Devil that was holding the girl was shocked of how quickly his comrades were taken down. He was about to flee when Flynn was already on him. With a single punch to the face, the Doom Slayer knocked several of the Devil's teeth, broke his noise and sent the demon flying while losing his grip on the girl, whom Flynn promptly caught. It was hard for Flynn to hold back, but he didn't want to scar the girl for life by being his usual brutal self.

The moment Flynn undid her bindings, the girl latched onto, bawling her little eyes out. Flynn froze at the contact, not out of disgust, but rather that it brought back old memories. In the past, whenever he had gotten scared, his parents would always be there to comfort him, before he lost everything. But that was a long time ago that Flynn had forgotten the touch until now. Slowly, his arms wrapped around the girl in a gentle hug. The Doom Slayer said no words, just held the child there as she cried into his chest. It was at the time Flynn noticed that the girl was not human, nor a demon. She had fox ears sticking out of her head and nine tails swishing around from her back.

 **[According to my memory banks, she appears to be a Kitsune, a fox-type youkai. By the number of tails, she is a Kyuubi]** VEGA commented.

Eventually the girl had stopped crying, letting out small hiccups. "You calm now?" Flynn asked.

The girl nodded, rubbing her head against his chest before being gently put down. The girl's cheeks were stained with dry tears and she rubbed some snot from her nose. Her clothes were a little messy, rumpled up and covered with dirt. Otherwise she looked okay. No cuts or other serious wounds on her face and body.

Getting to one knee Flynn asked, "So you got a name kid?"

The girl sniffed but managed to answer. "K-Kunou"

Flynn nodded. "Kunou, huh? My name is Flynn Blazkowicz. What did those demons want you for?"

His answer came when several people with black wings and crow heads, dressed like mountain hermits, appeared. They were carrying swords and spears "Get away from Kunou-sama!" One of them said. He and the others looked ready to attack.

Flynn frowned, preparing himself for a fight. But he was stopped when Kunou stood between him and the Youkai. "Wait! Please, he saved me!" Kunou yelled.

Her declaration made the Tengus pause, plus allowing them to notice the bodies of the Devils lying around them. Still they were cautious as they ushered Kunou over. The next few minutes consisted of Kunou explaining what had happened. As it turned out, she was the daughter of Yasaka, the same Yasaka that Flynn was supposed to see. Apparently there had been trouble happening lately in Kyoto and Yasaka had been busy lately due to it and thus Kunou had wanted to help. Somehow that had gotten her captured by those Devils who were a part of the problem, probably to lure out her mother. But on closer inspection, the 'Devils' were in fact demonic plants that had taken on the form of demons.

The leader approached Flynn and bowed his head. "Apologize, Blazkowicz-dono. Thank you for saving Kunou-sama. Yasaka-sama was becoming worried when we could not locate her." The Tengu said.

Flynn shrugged. "It wasn't much. Actually I need to speak with your leader regarding a missing magician by the name Lavinia Reni. Does it ring any bells?"

The tengu blinked his eyes, trying to recall the name. "Yes, I believe that such a person had come here to Kyoto. If you follow us, we can bring you to Yasaka-sama to speak more of the matter."

Flynn seemed unsure, but VEGA spoke up. **[While meeting with the Youkai leader is one of our objectives, the energy these plants are giving off is faint and quickly fading. I will not be able to pinpoint their point of origin if we follow them to meet with this Yasaka]**

"Sorry, but I can't meet with her right now." Flynn said to the Tengu. "I need to track down where these plant demons were going. They might lead me to the person I was originally searching for. I will however go to meet with your leader after I've dealt with the source."

The Tengu leader frowned at the answer, but could see the logic behind it. "Very well, we shall inform Yasaka-sama. And thank you again for rescuing Kunou-sama."

"Just make sure she gets home safe." Flynn said as the guards began to escort Kunou back to the palace. The young Kitsune looked back at Flynn, unsure. But the Doom Slayer gave her a reassuring wave before following VEGA's directions of the energy signature. The trail ended at an old warehouse on the outskirts of town. The entire place was covered in vines with numerous large multi-colored flowers. He even spotted a few demonic-looking carnivorous plants, looking like Venus Flytraps. Just as Flynn entered five meters of the warehouse, the plants began moving and attacked. The flowers fired seed like bullets while the flytraps opened their mouths and lunged at Flynn.

The Doom Slayer pulled out his Heavy Assault Rifle, attaching the micro-missile launcher and opened fire while dodging the attacks. Several 'seeds' were destroyed upon impact with the mini rockets, while the rest of Flynn's shots killed flowers or flytraps. Some of the vines latched out at Flynn, only to miss their target as the Slayer moved too quick for them to grab.

 **[Doom Slayer, I am detecting demonic energy inside the warehouse. I believe that this is the individual responsible for the demon plants that attempted to kidnap the young Kitsune]** VEGA announced. **[I am also picking up another energy signature, magic energy but human in origin, along with two objects, one holy and the other demonic near each other. I believe the human is Lavinia Reni]**

"Then let's not waste any more time." Flynn declared, putting away the HAR. He whipped out his gauss cannon in siege mode and took aim at the warehouse. The railgun fired, the projectile tearing through the vines and plants, blasting a large hole in the warehouse wall. Once the opening was made Flynn charged forward, dodging the attacks from the remaining plants. He then hopped through the hole and landed perfectly on the floor.

"Kukuku, looks like a little weed has stepped into my garden!" A male voice called out.

Frowning, Flynn looked up at a walkway. Standing there was a man with pointy grey hair, sharp teeth and wearing a long cloak, overall looking like someone from a vampire movie. Behind him was a closed door.

"Judging by your aura, you must be a demon, one of those Stray Devils right?" Flynn asked, while at the same time looking around for any hidden enemies.

The man cackled. "Correct! I left my master long ago in order to fulfill my lifelong dream…to fill the world with large breasts!" He declared proudly.

THAT almost made Flynn stumbled. "Wait, what?" Flynn asked, never having heard such a stupid goal. Even VEGA was temporarily suffering from confusion, unable to process this information.

"I love big breasts and as such, I will make the world only exist with women with large breast by taking out all of the small breasts in the world with my plant army!" The Devil declared. "I had originally came here to Kyoto to have my chimera absorb the city's leylines to grow large breasts, but when that big busty magician came, I decided to use her as a focus to grow my demonic plants. And once I have Yasaka and her large breasts I will-"

"Yeah, I heard enough of this crap." Flynn declared as he levered his gauss cannon. Firing, the weapon tore through the stray's legs, leaving only a bit of his thighs, as well as his left hand and forearm.

The Devil screamed in agony as he fell on his front. He wasn't bleeding as the heat from the blast cauterized his wounds. That meant little, however, as Flynn easily jumped onto the walkway. Putting one foot on the Devil's back, Flynn leveled his super shotgun at the stray's head. With hesitation, the Doom Slayer pulled the trigger and the Devil's head exploded into blood and gore.

"Well that was boring." Flynn commented as he decided to find the magician.

Shifting his focus, Flynn headed towards the door that the Devil was guarding. Obviously locked, Flynn tore the knob off and knocked the door off its hinges. It revealed a small room with only a single light from the ceiling. At the opposite end was a young woman hooked up to a chair covered with vines that seemed to spread outwards, even beyond the door. She had a voluptuous and busty figure and long flowing blonde hair, a few strands over her face. Her eyes were closed but the slow movements of her body concluded she was alive.

"VEGA, check her." Flynn ordered as he raised his right arm.

Having spent time learning more about his equipment, including his Praetor Suit and the AI, Flynn discovered he could manifest a body for VEGA. To be more precise, a way that VEGA could move in the real world while still linked to Flynn's soul, so even if the body was destroyed, no harm would come to either them. Flynn had selected the UAC drone.

 **[I can detect no physical abnormalities. However, I am picking foreign energy around her body, it might be some kind of spell to keep her submissive. My knowledge of magic is still far from complete]** VEGA stated as he continue his scan.

Suddenly the ground began to shake, followed by a loud roar. Insuring that Lavinia was okay the Doom Slayer rushed outside the room. Rising up from the floor was a large plant-like creature with dragon features. It paused as it looked at its creator's corpse and then glared at Flynn. Already deducing the killer, the creature released another roar.

 **[Judging by its appearance, this is most likely the chimera that the Devil had mentioned]** VEGA realized.

"Well, it's going to be joining its master." Flynn said. "Keep checking her, this won't take long."

Pulling out his chainsaw, he revved the engine before doing a jump towards the chimera. The monster roared as it lunged at the Doom Slayer, attempting to avenge it's master. However, it missed as Flynn put his foot on the beast's head, running over it before aiming at the monster's neck. The chainsaw's blade cut through the hard-wooden skin with ease, severing the chimera's head from its body. He didn't even pay notice to the green blood splotches on his jacket.

At that moment blue flames suddenly appeared. However they only covered the vines and plants, burning them to ashes. Unable to resist and with their master, the demonic plant life was quickly wiped out. Following that the warehouse's door opened revealing the Tengu soldiers from earlier along with additional forces. At the front was a woman who could be described as an older version of Kunou. She had a voluptuous figure and very long blonde hair with matching eyes. For clothing she wore the traditional shrine maiden attire, with a white coat over it held closed by a red ribbon and a golden crown on her head. Just like Kunou, she had a pair of fox ears sticking out her head and nine yellow tails swishing about gently.

Her golden eyes scanned the room before locking onto Flynn's form. Her eyes widened momentarily when she saw the monster's corpse behind Flynn, as did some of her soldiers, before calming down. "Greetings, might I assume you are Flynn Flynn Blazkowicz?" The woman asked politely.

"I am" Flynn replied, sheathing the swords.

"Allow me to introduce myself. I am Yasaka, the leader of the Kyoto Youkai and Kunou's mother. Thank you very much in saving my daughter and dealing with this threat. These demonic plant creatures had been attacking many female Youkai for the past few weeks but we had been unable to locate their source." The named Yasaka said as she bowed her head, unintentionally giving Flynn a good view of her large cleavage. "Tell me, what became of the mastermind?"

"Dead, his body, or what's left of it is up there." Flynn answered plainly. "The person I was looking for is also up there in a room. I think she's been put under some kind of spell."

Yasaka nodded, giving a wordless order to some of her soldiers who went off to retrieve the Lavinia. The Kyuubi looked back at Flynn. "If you could please come back to the palace with me, I would like to discuss about these events. Plus, Kunou will be happy to know you're unharmed."

 **(At the same time, Kuoh Town)**

"Buchou, I really don't think this is a good idea." Akeno said to her King and best friend. She, Rias and the rest of the peerage were standing outside Flynn's house.

Rias sighed. "I know Akeno. But this is our best shot." The redhead replied as she rung the doorbell.

After the whole incident with Flynn blowing up Riser's head, the Phenex third son had regenerated had was absolutely livid. Kind of understandable since anyone would be pissed off if their head got blown up. However, Grayfia stopped Riser from doing anything foolish, having already concluded that Flynn was someone far too powerful for the arrogant Phenex scion to mess with. Returning back to the engagement between Riser and Rias, Grayfia announced that both families have decided to let the topic be settled in a Rating Game between the two peerages. Riser, who had already participated and won several Rating Games, arrogantly gave Rias and her servants two weeks to prepare for the match, stating they would need all the luck they could get.

That was why Rias was here now. Even if the odds were against them of him helping, Flynn had proven to be far stronger than Riser. If she could convince Flynn to fight with them, or even train them, then their chances of victory would be higher. For as much as she was confident in her servants, Rias knew that they were no match against Riser. However, Rias was not expecting a blue hair beauty to answer the door. Followed by the same black cat to come running out and jump into a surprise Koneko's arms.

"Do you little Devils need something?" Tiamat asked with a frown as she crossed her arms. She looked at Issei who was staring at her chest, drooling. The Chaos Karma Dragon gave him a strong glare that snapped the pervert out of his trance. Tiamat could feel the presence of that bastard Ddraig in the boy's left arm but held back the desire to strike. While Flynn would not mind if she killed the Devil, he didn't want attention…yet.

Rias at first wanted to know who this person was. Despite her human appearance, the woman gave off a powerful aura far greater than all of their combined. If Rias was to guess this woman would be around Satan-class. But, the heiress got back on track. "Er…we're here to see Blazkowicz-san."

Tiamat raised a brow. "And why do you want to see master? I doubt the last people he would want to meet are Devils."

"M-master?" Rias questioned. As she concentrated her senses, the redhead Devil soon realized that the woman's aura was a dragon. "You're his familiar?" She asked, shocked at both Flynn even able to get one as well as having such a powerful familiar in the first place.

"That's one way to put it, but yes, I do belong to him." Tiamat commented. "Anyway, master is not here right now. He left to Kyoto on important matters."

"Kyoto? Why would Blazkowicz-senpai be there?" Kiba asked.

"As I said it is for important matters, matters that do not concern you Devils, so good day." Tiamat repeated sternly. She grabbed Kuroka, who hissed at being taken away from her sister, followed by the dragon shutting the door in front of Rias's face.

 **(Kyoto, Youkai Palace)**

Yasaka and her guards led Flynn to the inner part of Kyoto, where the majority of the Youkai resided. They soon arrived at the palace where a happy Kunou greeted them. The young girl immediately ran to hug Flynn, happy to see he was unhurt. "Flynn-san! Did you beat the bad Devil?" Kunou asked excitedly.

A bit taken aback by the girl's excitement, the Doom Slayer recovered a little and rubbed the girl's head. "Of course, demons are no match for me." He said reassuringly. He missed the smile on Yasaka's face at the sight of her daughter so happy.

Kunou nodded vigorously. She then proceeded to climb on top of his shoulders, much to her mother's amusement. When they arrived to a private room, Flynn discussed about what had happened to Yasaka while Kunou entertained herself by poking VEGA's drone body.

Yasaka sighed when Flynn finished his tale. "To think such a repulsive Devil had infiltrated our city. I can only imagine what would've happen if he succeeded with his plan."

"He probably kidnapped your daughter to draw you out. According to Mephisto you have control of the city's ley lines, which would've given that idiot more power to grow his plants." Flynn explained.

Yasaka nodded. "Indeed which is why I thank you again for your assistance. Concerning Lavinia Reni rest assure that we will make sure she recovers fully."

"I'm glad to hear that. I'd be rather peeved if she didn't make it because of that idiot's Mephisto's mistake." Flynn said. He ignored VEGA floating around the room away from Kunou, who was chasing after him.

"Speaking of which, am I to assume that you're not fully affiliated with him, but more of a freelancer?" Yasaka asked.

"That is correct." Flynn said. "Why do you ask?"

"If possible, I would like to hire you for future endeavors. Lately there have been problems among my faction and the Eastern Yokai Faction, both internal and external. Some of these problems require outside influence but not a part of a faction. Your presence would be a great help." Yasaka explained. "Of course, you will be compensated for your work."

 **[This could prove useful Doom Slayer. We cannot fully rely on Mephisto. Furthermore, it will allow you to be away from the demons in Kuoh, as I know you have been annoyed with them lately]** VEGA voiced as he floated above Flynn's head, where Kunou could not reach.

Sighing, Flynn agreed to Yasaka's request and got up. "Well, I guess I should be going now, seeing how my assignment is complete." Flynn said as he got up. VEGA's drone dissipated at the same time.

"What?! You're leaving!" Exclaimed Kunou, clearly upset. The girl had grabbed Flynn's leg, hoping to stop him.

Flynn gave one of his rare smiles as he ruffled the girl's hair. "Sorry kid, I got some people back home I need to make sure are not doing anything stupid."

"B-but you'll visit right?" Kunou asked. Her question surprised Yasaka. She did not seem to realize how close her daughter had gotten with the young man. Perhaps saving her life put Flynn in a positive light in the young Kyuubi's eyes.

Flynn frowned at the question. To be honest Flynn was still feeling uncomfortable. Not towards Kunou, but rather the emotions and memories he had long kept stored away. Still, he liked Kunou and coming to Kyoto will give him enough space away from those demons in Kuoh. "The next time I'm free I'll come and visit, promise." Flynn finally answered. "And I might be bringing a friend too."

That did some good to cheer Kunou up as she let go of his leg. Yasaka couldn't help but smile at seeing her daughter so happy. Due to her station, Yasaka rarely got time to spend with Kunou and because of her own status, the young Kyuubi made few friends. So it was nice to see Kunou become so attached to someone. And it looked like Flynn was quite skilled in dealing with children. Perhaps he has a younger sibling or something? Either way, the leader of Kyoto would be interested in meeting the human again.

 **And there we have it!** **Flynn has met Yasaka and Kunou. Hoped you all like what** **Flynn did to Riser. Next chapter will have a bit of bonding between the Doom Slayer and Kuroka. Also, remember the change in name and that Flynn does not have a Sacred Gear. I also hope that other people will post these kinds of crossovers in the future. I'm kind of thinking of doing a crossover between Doom Slayer and Gate, or maybe with Gears of War.**

 **Review!**


	7. Doom in the Underworld

**Again, glad so many of you are enjoying this story. Leave a review as usual and enjoy!**

 _"March unto their domain without pause. Wield your sword up high, only to be brought down when spilling the blood of the damned. For they would dare to take what is yours, to which they shall regret in their final moments."_

 _Corrax 3:40_

 **(Gremory Vacation House)**

"So, why exactly did you want to see me?" Flynn asked. The Doom Slayer was sitting on a chair in the front yard of Rias' vacation house in the outskirt of Kuoh. He had his legs resting on the table, not giving a damn about mannerism.

After coming back from Kuoh and dealing with a happy Kuroka smothering his face with her assets, Tiamat had told him what had happened. How Rias wanted to speak with him about what had happened at the clubroom. Normally, Flynn wouldn't have cared, but concerned if more demons were coming after seeing so many whores back then, Flynn decided to find out. That is how Flynn, along with Tiamat and Kuroka in her cat form, were now meeting with Rias Gremory. Also present were Koneko, whose lap Kuroka was currently resting on, Akeno who had brought out tea and snacks that neither Flynn or Tiamat were touching, and Kiba who was staying vigil. Issei was in the background, deeply bruised after his training session with Koneko, where said girl threw rocks at him, and was currently being healed by Asia.

"I suppose I should explain from the beginning." Rias said with a tone of seriousness. "You recall the blonde Devil from before?"

"You mean the one whose face I blew off and then regenerated?" Flynn asked rhetorically. "What about him?"

Rias sighed. "His name is Riser Phenex, the third son of the Phenex family. I'm also engaged to him in a political marriage. I don't think I have to explain why I absolutely refuse to marry him."

Flynn raised an eyebrow. Both Mephisto and Tiamat had explained to him that sometimes Devils arrange political marriages in order to strengthen bonds between pillars as well as keeping pure-blood Devils alive. It had happened sometimes with his people but was rare. And though he only seen him briefly, Flynn could understand why Rias did not want to marry Riser.

Taking Flynn's silence as a sign to continue, Rias said, "Due to my constant refusal to marry Riser, my family and the Phenex clan have made the decision that a Rating Game would decide if my engagement would continue or not."

"Rating Game?" Flynn asked, looking at Tiamat.

"It's a competition between Devils and their peerages. Normally it is used for entertainment and other times to increase one's social standing in the Underworld." Tiamat explained.

"And you want me to participate?" Flynn asked, a hopeful tone in his voice. A small sinister smile formed on his lips. The idea of legally tearing apart demons sounded very appealing. The Devils noticed this and shivered at the bloodlust radiating off him.

Unfortunately, Rias shot down that. "I'm afraid that's not possible. Unless approved of by both sides, outsiders cannot join Rating Games. And seeing how this is a special event and you're an outsider, I don't think the families will allow it. No, what I'm actually asking is for you to train us."

Flynn frowned, both at the fact he could not participate and what the Gremory girl was asking. "Train you? Why would you want that? Furthermore, why would I even agree?"

Rias sighed. "Because you are the strongest person we know. From the past Stray hunts, I have seen that, despite your brutality, you are a skilled fighter, more than any of us put together. With that knowledge, we could improve ourselves and have a better chance of defeating Riser."

"Well, it is true I am stronger than all of you put together." Flynn said, ignoring the glares from the others. "However, you didn't say what was in it for me?"

"If you help me, I would be in your debt. As the heiress of the Gremory Clan and the younger sister of the current Lucifer, it would be in my power to give you almost anything you want." Rias said honestly. She knew that usual tactics like seduction would not work on Flynn. Not when it was obvious that he held a strong dislike towards Devils. She would have to use connections and resources to get his help.

VEGA spoke up, communicating with Flynn privately. **[Assisting the Gremory may be advantageous for us, Doom Slayer. Not only would we have another source to requisition from, but we can gain better insight on the Devils in the event we must face them]** The AI reason.

To be honest, Flynn didn't like the idea of helping these Devils at all. But VEGA did make a good point that it would be better than relying just on Mephisto for materials and money. And when the time came to wipe out the Devils, Flynn would know everything he needed to know to face them. "Fine, I'll help train you." He saw the Devils with relieved looks on their faces. "First, show me how you guys are working on getting stronger."

 **(Two Hours Later)**

"I'll say it from the ass: You guys suck"

Those were the words Flynn said as he, the Gremory Peerage, Tiamat and Kuroka gathered in the living room. He had watched the training regimen the Devils were following, what they were trying to improve on and the strategies they were devising for the Rating Game. Needless to say, Flynn was not impressed. Even Night Sentinel recruits showed more promise than them.

"Screw beating that brat. You guys would be lucky to last half an hour against him and his whores." Flynn said.

Issei frowned. "Hey, what's that supposed to mean?" He demanded, not happy that his senior was dissing them and Buchou.

Flynn sighed. "Shup up and listen. VEGA, explain it." He told the AI, who currently had his drone form out.

 **[Very well. What** **Flynn is referring to is your training and current condition. There are many flaws in your plans and how you are trying to become stronger. First off is Rias Gremory: your focus solely on Power of Destruction. However, your power and speed are low that it is possible for opponents with abilities to protect themselves or immense durability to resist your attacks, or with incredible speed to dodge them. Thus, leaving yourself open for an attack up close, which is fatal given how you lack melee skills. Plus, your tactical skills are also lacking, including putting it into training. Having Hyoudou learn swordsmanship in just two weeks, when he would be more fitted as a brawler, is quite unwise]** VEGA said to the Gremory Heiress. The redhead wanted to retort, but knew he was right.

Next was Akeno. **[According to my understanding, the Queen Piece enables one to gain the traits of the Bishop, Knight and Rook. In your case, you depend solely on the Bishop's increase magic, and not speed, strength and defense. Not only does this make you unqualified to contend with fast moving or strong opponents, should you run out of energy or your magic is sealed, you are useless]** Akeno said nothing, not even her usual giggle.

After her was Kiba. **[Your speed is impressive, but that is all you have. You possess no sword techniques besides the basics, instead relying solely on your speed. Plus, you lack stamina meaning prolong fights are not your forte. There is also the case with your durability, which is basically non-existent]** Kiba frowned at that analysis but couldn't say anything in his defense.

VEGA looked at Koneko. **[Your problem is the opposite of his. Your defense and strength are average at best to the standard of Devils. However, you possess no range attacks, thus making you weak against long-range opponents and your speed is too low. Furthermore, if you face against individuals who also depend on strength and durability, the chances of you winning are 50% at best]** Koneko frowned and looked down.

Asia got her lecture. **[Seeing your personality and Sacred Gear, it would be ill-advised for you to learn any offensive techniques. However, your stamina is low, thus making it difficult for you to heal multiple people at once, along with the fact you must be next to them to initiate Twilight Healing. Plus, you have no defensive abilities or spells to protect yourself, thus making you more of a burden to the others.]** Asia seemed rather upset by the analysis, her eyes a bit watery, but Flynn and VEGA ignored it.

Lastly was Issei. VEGA's drone eye just stared at him for a minute before saying. **[As for Hyoudou…less said the better]** Issei's head dropped in shame, a depress aura over his head.

 **[Fortunately, I have worked out a training regimen for you all.** **Flynn shall take Hyoudou, Kiba and Toujou. Meanwhile Tiamat will train Gremory, Himejima and Argento]** VEGA stated.

"Tiamat…?" Rias murmured the name. Her eyes widened as she finally realized the blue haired woman's identity. "Wait! Tiamat, as in Chaos Karma Dragon Tiamat?! The strongest Dragon King?! That Tiamat?! She's your familiar?!" Those who knew what Rias was talking about were also shocked.

"Yeah, so?" Flynn asked, not the least bit bothered. "Just the heads up, I am going to be completely brutal in your training, to the point it might even kill you, leave you on death's door if you're lucky. Same with Tiamat. Still want me to train you?"

The Doom Slayer was radiating bloodlust that was freaking out everyone except for Kuroka and Tiamat. However, the peerage of Rias Gremory were determined to free their King from this forced engagement, even if that meant putting themselves at Flynn's mercy. "We accept!" They all said.

 **(10 Days before Rating Game)**

"Oh shit!" Issei cursed as he dodged another explosion. Another projectile came fly through and would've hit the pervert, if Koneko hadn't thrown a boulder at the projectile, destroying both in another explosion. "Thanks, Koneko-chan!"

"Move it pervert." Was all the girl had to say as more grenades came flying towards them. The two Devils ran as they avoided the projectiles.

What they and Kiba were doing was a practice exercise that Flynn had developed. The Doom Slayer would fire rockets and/or grenades at them, forcing the Devils to run for their lives while trying to reach him. This was to improve Koneko's speed and reflexes, Kiba's durability and stamina, and all four for Issei. It was also so that they could develop better reaction times for traps and ambushes. It had been an hour and so far, the trio had managed to avoid taking direct hits, though were covered in dust and bruises with their training clothes partially destroyed. Flynn was from an elevated position, a small hill overlooking the forest, firing his weapons without mercy. The young Devils have had no luck getting to the Doom Slayer. Even with the dense cluster of trees covering them, Flynn was somehow able to figure out their location, giving them zero chances to catch their breath.

While Flynn reloaded his grenade launcher, he looked at Kuroka. Said woman was in his Nekoshou form and resting on her stomach and elbows as her hands held her head. Using senjutsu, she was acting as his eyes in locating the three Devils. "So, when were you going to tell me that the white one was your sister?" Flynn suddenly asked.

The question was so sudden that Kuroka could only say, "Nya?" In response.

"The white-haired girl? Koneko, right? She's your sister." Flynn said.

Kuroka was still surprise that the Doom Slayer figured out the connection. She then laughed nervously. "Nyahahaha, was it that obvious?"

Flynn rolled his eyes as he fired another volley. "When you took my keys, it was so you could use my aura to hide yours while you snuggled on that girl's lap. And there were all those other times whenever she was around, you try to be near her as much as you could…plus, VEGA did a scan and noted that your DNAs matched above 50%."

Kuroka blinked, not realizing the obvious clues. "So, mind telling me why you two are in two completely different positions?" Flynn asked.

Seeing how she could not get out of this, Kuroka began her tale. "After our parents died, Shirone and I were taken in by a member of the Naberius Clan and I was reincarnated into his Bishop, nya. During the time, I became extremely talented in Senjutsu and Youjutsu, and with the Bishop pieces, my magical powers surpassed my former King, nya. Because of that, everyone assumed that I became drunk with powers and killed my King, nya."

"You don't seem insane. Though I'm not sure if I call your attempts to sleep with me sane." Flynn commented.

"That's because I find you sexy, nya!" Kuroka laughed. Flynn raised an eyebrow at the joke, but said nothing, waiting for her to continue her story. "The true reason as to why I killed him was to protect my Shirone, nya. The man wanted to conduct tests on her in his research of creating a Super Devil, nya."

"Super Devil?" Flynn asked, finding the name ridiculous.

 **[It is a name regarded for Devils whose powers surpass that of Satan-class. So far, there are only three known Devils who hold said position, two of whom are Demon Kings]** VEGA said.

"Yeah, and because of that my sister was nearly executed until she was taken in as the Gremory's Rook. It looks like my actions also made her refuse to use Senjutsu and Youjutsu, nya." Kuroka said. "It's not like I could bring her with me, nya. A child constantly on the run, I didn't want such a life for my cute little sister, nya."

"…I see…" Was all Flynn said. There was a faraway look in his eyes at hearing the girl's tale. It was far more noble than what he did, sacrificing his entire people to get his son, only to be betrayed. Kuroka might've not known it, but the Doom Slayer's opinion of her went up a bit. "By the way, what's Senjustu?" Flynn asked.

Kuroka blinked. "Senjutsu allows a person to control the flow of life energy or _ki_ in living beings. We can strengthen both our internal and external bodies or even cause plant life around us to bloom or wither, nya. An expert like me can sense the ki and auras of others from far away distances, which is how I evaded capture so far, nya. I can even change my own ki to hide from others, though its hard against powerful beings or master sensors. Though I'm surprise you don't know, nya. You've been doing it ever since I met you, nya."

It was true, when she first saw Flynn, she noted that he was passively absorbing large quantities of natural energy. She was startled of how much he was absorbing daily and not affected by it. And when she looked at his life-force, she was astonished of how large it was. The best way to describe it was it matched the energy of the world. And in some ways, Flynn was acting as a filter, absorbing the world's malice and negative thoughts into him, and yet remained completely sane. Not even Sun Wukong, a master Senjutsu user, could do that.

 **[Perhaps she is referring to the Argent Energy surrounding your body. It can be classified as your ki since it is generated from your body so much that it forms an armor around your body like a force-field and enhances your physical capabilities]** VEGA said through his private link to Flynn. **[As to why you're constantly absorbing natural energy, I can only conclude it is because of the Crucible, and the Elemental Wraith energies are like the energies of the world. So, technically you're not actually using Senjutsu, but something quite like it]**

"Who knows." Was all Flynn said to Kuroka as he fired another grenade. He was rewarded by a cry from Issei.

Neither of them noticed the phoenix hiding in the trees behind them.

 **(8 Days before Rating Game)**

Flynn had gone to see how Tiamat was doing. He left VEGA in his drone form to watch over the other three Devils who were currently sparring one another.

He found the dragon looking over the hill that lead to town. Walking up said hill were Rias, Akeno and Asia, the physically weakest members of the little band of Devils. All three girls were carrying large backpacks, filled with miscellaneous objects like rocks and sticks. Apparently, this was what Issei, Koneko and Kiba had to do when they were coming up the hill at the beginning of the training. Tiamat saw it as a good starting method for the three girls in improving their bodies and stamina by having them do this at the beginning of each session.

Ignoring the girls who were gasping as they were nearing the top, Flynn asked Tiamat, "So, how are they?"

Tiamat shrugged. "Hard to say. Their stamina leaves much to be desire but the King and Queen's demonic power are between mid to high class Devil. The Bishop is still low on all parameters. Still, I have to ask Master if it is really okay to be training these Devils? Especially the host of that bastard Ddraig?"

Flynn raised an eyebrow at the venom in her words. "I've been meaning to ask this, but what do you have against the Welsh Dragon?" It was only recently that Flynn learned Issei carried the spirit of one of the Heavenly Dragons, Ddraig's power being able to double the wielder's power and transfer it to people and objects."

"It was before the Great War, Ddraig had borrowed some of my treasure for his upcoming battle with Albion, the Vanishing Dragon. After the two were killed, my treasure was stolen by human thieves and scattered around the world. Ever since that happened, I've been chasing after the bastard and his possessors for a long time in order to retrieve my stolen treasure!" Tiamat answered with a growl.

"Must've been some valuable treasure." Flynn commented.

"Ah! Ah, yes it was…" Tiamat muttered shamefully. For some reason she was unable to look at Flynn after that, as if trying to hide something.

 **(4 Days before Rating Game)**

Flynn sighed as he sat down on a chair. Presently he was watching Tiamat sparring against the Devils except for Asia, Kuroka had gone and wander off as she usually did. VEGA had suggested the idea of a spar to see how much the young Devils had improved and work on their teamwork. Flynn was going to volunteer, but VEGA managed to convince him not to, since there was a good chance he might 'accidentally' kill the Devils. Thus, Flynn was stuck watching as Tiamat beat the five Devils with ease.

' _So, what do you think their chances are?'_ Flynn asked VEGA.

 **[Hard to say. From the recordings of Riser Phenex's previous matches, the man has a full peerage, but the only true threats are himself and his Queen. However, there is no doubt that the rest of his servants are experience. However, these six Devils each have their own unique skills but are still inexperience. Hypothetically, they have a 50/50 chance]** VEGA responded.

Flynn nodded, agreeing with that assessment. As he watched Tiamat throw Issei into a tree, his phone rang. Pulling it out from his pocket, Flynn read the caller ID and saw it was Mephisto. Making sure Asia was completely focus on the match, Flynn answered. "What?"

" _Doom Slayer, I trust that everything is going well with the young ones? Didn't kill them yet, did you?"_ Mephisto asked with a chuckle.

"Quiet wretch. Did you do what I ask?" Flynn growled.

" _You mean about the Black Cat and her story? Yeah, I did some research and looks like_ _Naberius member was trying to create a Super Devil. In fact, he was affiliated with the Old Satan Faction too. I managed to recover enough evidence that not even those old crones in the Devil Council could refute it."_ Mephisto answered. _"Call me curious, but why were you even asking about this? Oh my, don't tell me your falling for the cat's woes~?"_

Flynn growled. "Watch it. I just did it because I could possibly mock these Devils for their incompetence."

Mephisto chuckled. _"Yeah, yeah, whatever you say Doom Slayer. I'll have the documents sent to you later. Oh, and Lavinia finally came back. She says hi and thanks."_ With that last part, the Demon hung up.

Flynn sighed. He looked back at the spar and saw that it was almost over. Issei had been beaten pretty badly after trying to grope Tiamat's breasts and was currently unconscious. The others were also rather roughed up and looked exhausted. Asia was already heading over to heal them.

Why couldn't life return to normal? Slaying demons was far easier than dealing with all this crap.

 **(Day After Rating Game)**

It was the evening, and Flynn was doing a final patrol of the town on his motorcycle. With the Gremory Peerage doing their Rating Game and the Sitri Peerage not really being much help, exterminating any threats to humanity was left to the Doom Slayer. So far, he had killed three Stray Devils on separate occasions. Just like the previous ones, they were all horribly mutated, insane and no challenge whatsoever. To be honest, the Imps of Hell put up a better fight than these strays.

"At least the grocery store was open." Flynn muttered as he drove back home. Though he didn't really need food, he still had Tiamat and Kuroka unfortunately to feed. Last time he remembered, Kuroka was napping back at the house, and probably still was now. Strangely, Tiamat was absent this whole day, saying she had something to do and left quickly.

As Flynn turned the last corner towards his house, he frowned. Having raised to be a warrior and fought for eons, the Doom Slayer had developed akin to a sixth sense. And right now, as he neared his house, said sense was going off. Everything looked normal, but Flynn could not shake the feeling something had happened. His suspicions were backed up when VEGA spoke. **[Doom Slayer, I am detecting traces of demonic energy from within the house. As if a demon had been using its powers recently]**

Parking his bike, Flynn pulled out his super shotgun and made his way to the front door. Not much to his surprise, the door was unlocked, in fact, when Flynn pushed it back, the top hinges fell off, causing the door to bend slightly. What greeted Flynn was a mess. Nearly the entire first floor of the house was in shambles. Furniture was knocked over and destroyed, the floor, walls and ceilings showed signs of slash marks, burns, cracks and other evidence of a fight. Finally, there was no sign of Kuroka.

Immediately, Flynn summoned VEGA's drone body. The AI began scanning the entire house. After a minute he spoke. **[I cannot fully identify these signatures, but they match those of the servants of Riser Phenex. I will look at the security cameras]**

Said cameras had been installed at Flynn's request. He didn't want to take any chances of someone having sneak in, like what just happened right now. The Doom Slayer watched as VEGA materialized a holographic image. Said image showed Kuroka lounging on the sofa bed in the living room. Suddenly, Riser and his peerage came barging in, startling the Nekoshou. After that a fight broke out. Kuroka had managed to defeat most of Riser's servants but was eventually overwhelmed by the Phenex and a woman VEGA identified as Riser's Queen. After that Kuroka was bound by magical seals and teleported away.

"Hmm, so that's what happened." A voice from behind said.

Spinning around, Flynn pointed his shotgun at Mephisto's face. The demon had a calm look on his face, not perturbed by the weapon. Seeing who it was, the Doom Slayer slowly lowered his weapon.

"What do you mean?" Flynn demanded.

"Well first off, you should know that the Gremory peerage lost the Rating Game." Mephisto said. "It was pretty close, though. Those kids managed to defeat all of Riser's servants and by the end of the match only the Gremory Heiress, the Phenex and the Red Dragon Emperor were left. Gremory would've won if Riser hadn't taken her down with a surprise attack. After the match, the boy and his peerage disappeared for a while before returning to the Underworld."

"That doesn't explain how they knew Kuroka was here. Or why they captured her?" Flynn commented.

Mephisto shrugged. "Riser was probably spying on Rias during their training and must've seen Kuroka. Even though she's of Ultimate Class Devil strength, Riser is quite strong himself and his Queen has the power of a High-Class Devil. Still, they must've used some serious tricks to surprise the Black Cat, who is skilled in detecting people's ki. My guess is that he wishes to show his capture of her at the engagement party, to solidify his position as the future son-in-law of the current Lucifer. The real question is: what are _you_ going to do?"

Flynn frowned. What was he going to do? To be honest he had no reason to save Kuroka. And yet…her story had done something that moved the Doom Slayer, to sacrifice everything to save the one you love, even earning said person's hatred. That, and Flynn had to admit that the Black Cat had grown on him. Gripping his weapon, Flynn looked at Mephisto. "Can you take me to the Underworld?" He asked as he made plans to contact Tiamat.

The demon smirked. "I had a feeling you would ask that."

 **(Gremory Mansion, Reception Hall)**

Many Devil nobles had gathered. Those who had close ties with either the Gremory or Phenex Clans, others hoping to gain favor with said clans or some of the other nobles. Also present were the members of those two clans as well as three members of the Satans. Everyone was enjoying to party, having the drinks and food made available or conversing with one another.

Three members of Rias' peerage were also present. Kiba, Koneko and Akeno, all dressed in formal attires, were standing near one of the building's corner. Unlike the rest of the occupants, they did not feel any joy. Only shame and anger at their failure to free their King from this engagement.

All activity stopped when a large pillar of fire appeared on the stage. When it died down, it revealed a triumphant Riser Phenex, dressed in a flamboyant white suit glittering in the light. Beside him was Rias Gremory, wearing a white wedding dress that enhanced her beauty. Her expression was the opposite of Riser's, her gaze downward.

"Greetings, my fellow Devils. Riser is honored that you have all come for my engagement!" Riser said out loud, earning applause from the Devils. "However, I can tell that there are some among you who do not approve or cannot accept me as the husband of Rias Gremory. And I agree, after all, she is the younger sister of our esteemed Lord Sirzechs Lucifer."

His words had some murmurs among the crowd. Even Rias was looking at her fiancé in confusion. What was he up to?

"Thus, I decided to prove my worth. It was only by chance did Riser discover a certain dangerous criminal hiding in the very town my fiancée governs." Riser snapped his finger and another pillar of fire appeared beside him. This one revealed his two Rooks and Queen standing proudly. What caught everyone's attention, however, was the bound Kuroka. Said Nekoshou was on her knees, her skin slightly bruised, her clothes torn, and her neck and wrists bound my magical cuffs, cutting her off from her power. She growled, glaring at Riser.

Many Devils were shocked to see an SS-class criminal here, captured, but none so than said criminal's little sister. Koneko had dropped the plate she was holding, slowly backing away. Her golden eyes widened in shock, memories returning that she would rather forget. Koneko was so shaken that she didn't even register Akeno and Kiba trying to console her.

Before Riser could make any more boasts, the hall's door was slammed open. Running into the room was a certain perverted Pawn. "BUCHOU!"

Issei Hyoudou's scream made the devils in the room turned their heads to look at him with wide eyes before everybody burst into shocked chatter. Rias also looked at Issei with wide eyes, she didn't expect him to come here shouting like that. "To all the High-class Devils here! My name is Hyoudou Issei of Kuoh Academy and Pawn of Rias Gremory-sama! I have come to take Buchou back!" Issei declared as the door closed behind him.

"Ise!" Rias shouted with joy.

"You!" Roared Riser in anger.

The Pawn of Rias Gremory glared at Riser right in the eye. Walking up to the center of the room, he declared with a loud firm voice, "Riser Phenex! I won't let you marry Buchou! Her virginity belongs to me!"

You could hear a pin drop at that declaration. Even Kuroka, who had been secretly hoping that it was another certain person, stared at the Pawn in bewilderment. Soon, Devils were talking out loud, asking questions, demanding to know what was going on.

"Calm down everyone, this was an event I organized." A male voice said.

Walking forward, Sirzechs Lucifer got everyone's attention. Behind him was his maid, wife and Queen, Grayfia Lucifudge.

"Lord Lucifer! What are you talking about?!" Riser asked, trying to be respectful at the same time.

Sirzechs smiled. "You see, I wanted to see the power of a Dragon, so I asked Grayfia to bring the boy here." There were a few outcries at this irresponsible act, but Sirzechs spoke above them. "The Rating Game from last time was very entertaining. But it was a bit disadvantage for my little sister who had no experience to face off against Riser who is a prodigy from the House of Phenex."

"Are you saying you found the game unfair, my lord?" Lord Phenex, Riser's father, asked.

"No, no, not at all. If a Satan such as myself says such thing, then I would be making the old nobles look bad. The connection between the High-class Devils is important after all." Sirzechs claimed.

"Then, Sirzechs, what do you intend to do?" An older man with red hair like Rias and Sirzechs asked.

SIrzechs smiled at him. "Father. I want to make my cute little sister's engagement party into a flashy one. Dragon versus Phoenix. Don't you think it's the ultimate event? To stir up the party by having a battle between legendary creatures. There aren't any entertainments which can surpass it."

No one said anything as they took his words in, still looking at the redhead Devil. Sirzechs then moved his sight towards Issei. "Red Dragon Emperor, you have our permission. Riser, can you show your power once more right in front of Rias and I? I would like to see the strength that managed to capture the elusive Black Cat."

Hearing the words from the most powerful Devil, Riser made a fearless smile. "Very well. There is no way I can decline if Lord Sirzechs asks me. This Riser will show his last performance before getting married!"

Sirzechs nodded and looked back at Issei. "Now then, Dragon user. What prize do you want if you win?"

"You cannot be serious Lord Lucifer!" A Devil shouted, followed by several others. They were silenced when Sirzechs raised a hand.

"He's a Devil, so we need to give him something fitting for it since we are asking him to do something for us." the Satan smiled. "Now then, I can give you anything. A Peerage? The most beautiful women? Wealth?"

Issei thought about his options before saying, "I want you to give me Rias Gremory-sama back."

Sirzechs nodded, a happy smile on his face. "Very well. Should you win…"

A loud BANG from outside happened, startling everyone and cutting off Sirzechs. Following it were more gunshots, as well as the sound of crashing, cries of pain and terror and other rather uncomfortable noises. The Devils became tense for some reason. A guard finally burst through the doors, shutting it quickly behind him.

"Just what is going on now?" A tall muscular Devil with black hair asked.

"Lord Lucifer, there is a human invading!" The guard shouted. This made the Devils all gasp in shock, with even Sirzechs looking surprise. Kuroka looked up from the floor, her golden eyes wide before a smile formed on her lips. "He just charged through and is shooting, punching and kicking anyone who gets in his way. We can't stop him, he's-"

The guard's rant was cut off when the large doors were destroyed, being ripped off their hinges. The guard was sent flying, crashing into a table.

Killing intent began to fill the room, make all the Devils shiver. Even the ones who were High-class, Ultimate-class and even Satan-class. Slowly walking out of the smoke was none other than Flynn Flynn Blazkowicz. In his right hand was his super shotgun, while his left hand was dragging a guard by the back of their clothes. It was hard to tell if the Devil was conscious or not, given the injuries he had. Suddenly the smoke was cleared when a large, blue Western Dragon popped her head through. Her cold aura swept throughout the hall. Tiamat released a loud roar that caused the weaker Devils to be knocked off their feet.

Flynn surveyed the room with his eyes. His gaze made the Devils instinctively take a step back, feeling dread for reasons they could not explain. Finally, after what felt like an eternity, Flynn said,

"I'm here for my cat."

 **There you go everyone! The Doom Slayer is in the Underworld. Next chapter will be Flynn pounding the blood and other stuff out of Riser. Be sure to leave a review!**


	8. Phoenix Beatdown

**What you've all been waiting for! A beat down courtesy of the Doom Slayer. Followed by some more revelations. Anyway, be sure to leave a review!**

 _"Full of arrogance, they believe none can stop their crusade. Yet they now know the folly of such pride, for you now stand before them. Fist clenched and eyes firmed, you meet them head on. Mountains of their corpses shall be made by your hands, the landscape will be forever changed, as even the mightiest of their legions and champions will fall before your wrath."_

 _Corrax 5:20_

 **(Gremory Mansion, Reception Hall)**

Silence filled the hall as this human walked through the hall. Flynn tossed aside the surprisingly still alive guard like a piece of garbage. Tiamat stood proudly above him, her watching the Devils fiercely. Said Devils were still stunned by Flynn's exclamation. Some had expressions of confusion, others with anger. However, one of them eventually broke the silence and was of the latter.

"Who do you think you are?!" Ravel Phenex cried as she marched towards Flynn. Memories of how this human blew up her brother's head filled her mind and she could not hold back her anger. "Who are you, to challenge big brother?! Human trash!" She fumed.

Her outcry made other Devils speak out in anger at the audacity of this human. However, Flynn was in no mood to deal with this and without even looking, fired his super shotgun at a random Devil. Said Devil's left leg was blown off, it's remains and blood flying everywhere. The Devil fell to the floor, writhing in agony as he screamed, clutching the remains of his leg. This single action caused silence resume once more. Flynn looked back at Ravel, his trademark glare set on the young Phenex. Said girl had lost her rage and bravado, now replace with fear. Upon seeing that glare, Ravel backed away, trying to remain out of sight.

Focusing back on the main crowd, Flynn repeated himself, "As I said, I'm here for my cat. And if none of you idiots can understand, I'm referring to the girl with the collar around her neck." He pointed towards Kuroka.

It was at that moment Sirzechs decided to speak up. "Excuse me. While I'm willing to entertain the idea of letting you fight Riser Phenex. I must tell you that handing over the Black Cat is impossible."

"Lord Lucifer! Don't tell me you're actually going to listen to this human's demands!" Riser exclaimed, shocked at the redhead's words.

Flynn looked at Sirzechs, studying him intently. Indeed, he was powerful, perhaps on the same level or greater than an Arch-vile or Tyrant. However, to the Doom Slayer, that wasn't very impressive.

"I'm afraid that young Riser is right, Sirzechs." Zeoticus, the father of Sirzechs and Rias, said. "Besides not being a Devil, the boy does not have any political support. Endorsing the idea to let him face Riser is impossible."

"I believe I can help with that." A new voice spoke.

A magic circle suddenly appeared in the middle of the hall, and out from it was none other than Mephisto, complete with his cane and a purple top hat. He did a dramatic bow to the audience as the Devils all gasped, recognizing the famous individual. "Been a long time since I've last been to the Underworld."

Sirzechs blinked, not suspecting to see the Ultimate-Class Devil here. "Lord Mephisto. It's quite rare for you to come to the Underworld. Do you know this boy?"

"Indeed, I do, Lord Sirzechs." Mephisto said. "I found him a few months ago, unconscious and wounded. Thus, I took him in. I guess you could say I'm his caretaker, guardian, however you like to put it." He smirked when he heard Flynn snort. "As such, I believe I can be the 'political support' Lord Gremory mentioned. I'm sure that will be satisfactory for everyone here."

Sirzechs glanced at the Devil who got his leg blown off. Others were already using magic to stop the bleeding. He then looked back at Flynn. Mephisto's presence certainly explained the boy's knowledge of the supernatural. But it wasn't just that, something about Flynn unnerved Sirzechs. It was the same feeling that he had when he went to inspect the Familiar Forest. The redhead Satan had a feeling that if even he refused, Flynn would take back Kuroka through force. Also, this was a chance to watch this boy in action. "I suppose that would make Mr. Blazkowicz suitable to challenge Riser. However, regarding his demands to free the Black Cat, I'm afraid that would be difficult as I previously mentioned. She is a wanted SS criminal for killing her King."

Flynn snorted. "So, killing a fucker that would've done twisted experiments on her younger sister makes her a criminal? Is that what you're saying?"

His words made Sirzechs frown and gaining the attention of the other Devils. Among them was Koneko, who was surprised for this new revelation of her sister. Didn't Kuroka kill their old master out of a lust for power? As if answering the unasked question, Flynn pulled out a book that Mephisto had given him and threw it at Sirzechs.

The Lucifer opened, skimming its contents. His frown deepened at he read more and more. "Lord Naberius was running experiments on live subjects to create a Super Devil?" He read aloud, earning shocked gasps from the crowd.

"Most of which ended in failure where the subjects died horrible deaths." Mephisto added. "Plus, it seems he was getting support from the Old Satan Faction. I don't think I'd have to explain how bad that would be if he succeeded."

Some murmurs were going on now, mostly about the Old Satan Faction. Sirzechs re-read the book several times, trying to find any evidence of false. When he found none, he released a tired sigh. "It appears that the case on the Black Cat Kuroka will have to be investigated. Flynn Blazkowciz, should you win, you will have claim over her. Should you lose, Kuroka will remain in custody until we can sort out this mess. Riser Phenex, do you agree to this?"

"Of course, Lord Lucifer! I will gladly put this pathetic human in his place!" Sneered the Phenex.

"Hey wait a minute! What about Buchou!?" Issei shouted, a little annoyed that everyone was focused on Flynn.

Flynn spared the pervert a glance. "What about her?" He asked in a disinterested tone.

Issei glared at him. "Aren't you going to save her too?!"

"Why would I? Not like she's someone important." Flynn shrugged off.

' _Damn that was mean.'_ That was the thought most of the occupants in the hall had.

"Well then" Mephisto said, getting everyone's attention. "How about we make these two vs two then? Better yet, let's have all of Riser's peerage participate too. And why not have this fight be broadcasted among the Factions."

Sirzechs frowned. _'Just what are you planning Mephisto?'_ He thought as he looked at the ancient demon. "And why would you want that, Lord Mephisto?"

Mephisto smirked. "Why, for entertainment of course. It is rare that we get the chance to see such a battle. Think of the number of viewers we could get by broadcasting this?"

Sirzechs noted that some of the other Devils were murmuring in agreement, and Riser seemed just as satisfied, no doubt wanting to use this moment to stroke his ego and spread his name. With that, Sirzechs sighed. "Very well then, it has been decided! A rating game will occur between Riser Phenex and his peerage against Issei Hyoudou and Flynn Blazkowicz! Should Issei and Flynn win, then Rias Gremory will be free from her contract and Kuroka will be absolved of her crimes. Should Riser win, Rias will marry him and Kuroka will remain detained in the foreseeable future. The game shall be broadcast to all Factions. Let the game begin!"

With that declaration, a bright red light enveloped the said contenders as they were swiftly teleported to the stadium. As the Devils prepared to watch the match, Tiamat had reverted to her human form and made her way over to Kuroka, the Nekoshou still on her knees on the stage. Glaring at some nearby guards, making them step back, Tiamat burned off the shackles without harming Kuroka. "You always seem to be causing trouble for master, cat." Tiamat scolded.

Kuroka grinned sheepishly. "Nyahaha, this time it wasn't intentional." She replied. "How did you guys get that journal?" She had recognized it as her former King's personal journal, thought lost after she had murdered him.

"You can thank Mephisto. Master asked him to find evidence to clear you of guilt. Somehow, he managed to get that journal along with a few other items." Tiamat huffed. "It's quite rare for Master to do something like this. Guess your situation really moved him."

Kuroka blushed at the fact that Flynn had gone out for her. Her blush faded when she spotted her sister from the corner of her eyes. Koneko, or Shirone, was being supported by Rias and the rest of her servants. The young Nekoshou's eyes also locked onto Kuroka's but she quickly looked away, unsure of what to feel right now. That made Kuroka feel sadness inside her heart.

Tiamat saw all this and decided to pity the Black Cat. "Come, let us watch as Master burns that fool in his own flames."

 **(Grigori)**

"What are you doing, Azazel?"

The question was asked by Vali, a silver haired young man. He was inside the office of Azazel, the Governor-General of the Grigori. Said man, with brown hair and blonde bangs, was looking at a wide-screen TV hanging from his office's wall.

"Oh, Vali. Perfect timing." Azazel said from his chair. "Looks like Sirzechs is broadcasting a match right now. It's between the third son of the Phenex Clan and his peerage against the current Red Dragon Emperor and a human."

That caught Vali's interest. As the White Dragon Emperor, he was destined to clash with the wielder of the Red Dragon Emperor. This was a good chance to see what his so-called rival was capable of. However, he was curious as to why a human was participating. "Interesting, but who is the other person? The human?"

"I was wondering that too. They would have to be a magician or Sacred Gear wielder. The kid's name is Flynn Blazkowicz. Apparently, he's been under the care of Mephisto Pheles. Which is weird because he hasn't been part of Devil politics since the war ended." Azazel explained.

The name Mephisto did indeed catch Vali's attention, but it was the human's name he was focused on. As a secret member of the Khaos Brigade and the leader of the same team Kuroka was a part of, Vali knew that Ophis had sent the Nekoshou to spy on Blazkowicz. When he asked, Ophis did not reveal anything, except saying she has been waiting for him. Whoever Flynn Blazkowicz must be of great importance to catch the Infinite Dragon God's eyes. Perhaps watching this match will prove more interesting than he thought.

 **(Kyoto)**

Mother and daughter were currently enjoying dinner. While Yasaka was eating in a regal manner, Kunou, as with all children, was eating quite fast. She was stuffing food either in her bowl or in her mouth.

"Kunou-chan. Please slow down. I don't want you getting sick." Yasaka chided her daughter.

Kunou looked embarrassed, swallowing the meat that was in her mouth. "Yes, Ka-chan." She replied meekly.

At that moment a Tengu entered the room. Bowing to Yasaka and Kunou, he said, "Forgive me for interrupting your dinner, Yasaka-sama. However, I thought that you should know that the Devils are broadcasting a match right now. Blazkowicz-dono is one of the participants."

That got Yasaka's attention. Ever since the incident, Kunou had been wanting to meet Flynn again. Though the human was unable to come to Kyoto due to school and work, he did send letters every now and then. She hadn't expected that Flynn would be taking part in one of those Devil competitions. Kunou, however, seemed excited that she nearly jumped up. "Ka-chan! Can we watch? I want to see Flynn-nii! Can we? Can we?"

Seeing her daughter's excited expression, Yasaka giggled. "Okay, okay." She turned towards the Tengu. "Could you please bring up a visual for us to watch."

"As you command, Yasaka-sama." The Tengu replied. He was also curious about how Flynn would fare. In fact, some Youkai had taken an interest in the human who helped them deal with that perverted Devil and save their princess.

 **(Heaven)**

"It seems that the Red Dragon Emperor has sided with the Devils." Michael, Archangel and leader of Heaven after God's death, said.

With him was his sister Gabriel, along with Raphael and Uriel. Together, they made the Four Great Seraphs, the strongest and highest ranked members in Heaven. The two angels were watching a screen showing, the combatants appearing on a wide battle arena.

"That does indeed seem to be the case. However, it is surprising that Mephisto is a part of this. I don't recall him ever taking part in a Rating Game, even after he turned the Dragon King Tannin into his Queen." Gabriel commented.

Michael nodded. Mephisto was one of the two remaining Demons who had left Hell after Satan began slaughtering those who would try to usurp his rule. Despite being labeled as an Ultimate-Class Devil, Heaven was weary of Mephisto more than the current Satans, due to his tricky personality…and other reasons.

Michael's attention shifted to the sole human among the participants. He did look physically fit for a human, but besides that Michael could see nothing of interest. Nothing that stood out. "What was the human's name again?" Michael asked no one particular.

It was Raphael who answered. "If I recall, the announcement said it was Flynn Blazkowicz."

Suddenly Gabriel gasped, holding a hand to her mouth. This did not go unnoticed by the others. "Something wrong, Gabriel?" Uriel asked.

"It's nothing Uriel. Except." Gabriel's eyes seemed to focus more on Flynn. "I can't help but feel like I seen him from somewhere."

Michael frowned and looked back at the screen. "Well, let us watch and see if we learn anything new."

 **(Rating Game Arena)**

The participants had all fully arrived in the arena. Said arena was a wide, rectangle-shaped field. On each corner were large King Pieces. And on one end were Flynn and Issei, while in the other was Riser and his peerage.

 **[After running testing scenarios, I've concluded there is no reason for you to use the Praetor Suit. Furthermore, we should wait until you reveal your true identity, as the armor will no doubt give it away]** VEGA noted.

Flynn said nothing but cracked his neck in anticipation. He glared at Issei when the pervert looked like he was going to speak. "Just to be clear, we are not teammates here. Get in my way and I won't hesitate to take you down." Flynn warned.

Issei gulped and nodded.

A large holographic screen appeared above them, showing Sirzechs' face. "The field has been declared enemy territory for both sides. Thus, all Pawns are able to promote. The match will end once one side is completely defeated. Understood?"

While all the Devils were listening, VEGA had spoken to Flynn. **[Realizing that this is being broadcast live, there is a 78.95% chance that young Kunou is watching]** The AI said.

Flynn internally grimaced. _"Guess that means I need to water down the violence here."_

"Then begin!" Sirzechs declared.

Riser immediately took to the sky, wings of fire popping out from his back. "You girls deal with the human trash! The other trash is mine!" The Phenex declared.

"Yes, Lord Riser!" His Peerage replied.

"Fine than you Yakitori! Let's go!" Issei shouted as he promoted himself to [Queen]. He then raised his left arm, Boosted Gear appearing.

 **[Balance Breaker! Welsh Dragon Scale Mail]** A voice shouted from the gauntlet. In seconds the boy was covered in a red draconic armor with what looked like thrusters on the back. He then took off and engaged the Phenex in close combat.

 **[How fascinating! This must be the Balance Breaker that Mephisto mentioned]** VEGA said in curiosity as he and Flynn watched Issei fight Riser. **[However, my scans are showing that it is not fully complete. Perhaps it will reach its true form in time]**

Flynn had to agree. The armor was quite impressive. If given enough time, Issei might be on the same level as a Prowler.

"Prepare yourself, human scum!" A female voice brought Flynn back to see a short girl with a human staff charging at him. "You will pay for your insolence towards Lord Riser!"

To a normal human, her speed would've put anyone of them to shame. But to Flynn, she may as well have been crawling. Without any hesitation, Flynn struck out his left arm lightning fast. The back of his hand hit the girl in the cheek so hard that she was sent flying right into the walls surrounding the arena. The impact caused the wall to crack as the girl coughed up blood. Seconds later she dispersed into light.

" _Lord Riser Phenex's 1 Pawn retired"_ A voice announced.

The rest of the peerage were shocked of how swiftly one of their own had been taken out. Unfortunately, they had no time to gawk as Flynn was already upon them. Grabbing the faces of the two closes girls, the ones in maid outfits, Flynn slammed them hard against the ground, forming small craters upon contact. He then followed it up with a powerful hook kick to the belly dancer's face, sending her flying just like the first one. All three girls disappeared in green light.

" _Lord Riser Phenex's 3 Pawns retired. Medical care is required"_ The same voice announced, this time unable to hide its shock.

The surprised continued when two girls, twins, lunged at Flynn from both sides. They each had chainsaws already revved up. Flynn merely brought out his own, larger chainsaw and parried the girls just as two Neko Girls attacked from the front. But it was pointless as Flynn quickly swung his chainsaw at them, slashing through their flesh and causing blood to fly out from their stomach where they were hit. The Neko girls cried out in pain as they disappeared. Flynn then followed it up by pulling out a detonating cord and wrapping it around the twins. Once they were securely held, Flynn detonated the cord, engulfing the girls in an explosion.

" _L-Lord Riser Phenex's 4 Pawns retired. Medical care immediately!"_

 **(Devils)**

Everyone was gaping at the scene before them. At first, their attention was solely on Riser and Issei's match, but the moment the announcement came in, the image shifted to Flynn as the human demolished all of Riser's Pawns, in just ten seconds! That wasn't possible for a human to do, especially since all the Pawns had promoted to Queen the moment Sirzechs made his announcement. And he did it all with brute strength.

Rias and Sona's Peerage were also in shock. Though they knew Flynn was strong, they had never seen him in action, only the remains of his battles with Stray Devils and the slaughter of the Stray Exorcists and Fallen Angels. But, to see him fighting for the first time, they soon realized just how much Flynn outclassed them. He used no magic, no Sacred Gear, just pure fighting prowess to completely demolish half of a peerage who had won several Rating Games in the past. Despite that, they knew that the match wasn't over yet.

To the side was Zekram Bael, the founder of the Bael Clan and progenitor for their famous Power of Destruction. As such, he was one of the two oldest Devils alive and thus, like Mephisto, was originally a demon from Hell. When Satan began his 'purge' of any force that would try to oppose him, Zekram did not hesitate to join Lucifer and the other surviving Sins in leaving Hell for the Underworld. The then Head knew it was a risk but better to face death at Satan's hands. He knew the history of the Devil race after they left Hell, after all, he was there for all of it. Zekram also knew that many of their legends were in fact true based off events that actually happened. But none of that explained the emotion he was feeling right now.

The moment this person, this human, entered the reception hall, proclaiming to have come for his 'cat', alarm bells went off in Zekram's head. Sweat began to slide down his face, arms and hands. Every nerve in his body was screaming at him to flee, to run as fast as he could. Old nightmares began to stir inside of him, nightmares Zekram had thought were long gone. Then he looked at the 'boy's' eyes, those red eyes that screamed rage and pain no living being could ever possess, not even gods. It was only when he watched Flynn wipe out half of Riser's peerage did a horrifying thought came to mind. _'No, it's impossible. He couldn't possibly be…no, he was sealed away eons ago! No one, not even the Seraphs could reach his tomb!'_ Zekram thought as he focused on the screen.

 **(Back with** **Flynn)**

Ravel was the first to snap out of it. "Everyone! We have to focus and not allow ourselves to be distracted!" She shouted to the remaining girls. Bringing out her flame wings, Ravel took to the air. "Karlamine, Isabela, Siris, Xuelan! Engage him at close range! Yubelluna, Mihae, with me to provide range support!"

"Understood, Lady Ravel!" The remaining girls cried. The one in the kimono and the purple-haired one took to the skies alongside the Phenex. The remaining four girls rushed at Flynn from all sides. When they were halfway close, the three in the air fired a barrage of projectiles consisting of magical bullets and fireballs. Flynn dodged all of them as he rushed towards the four girls.

Xuelan was the first to fall. She struck out with a leg kick, only for Flynn to dodge and grab said limb and twist it painfully. Then, throwing her over his shoulder, Xuelan landed on the ground with a loud thud. Flynn followed it up with a shotgun to the stomach. Siris tried to take him down with her Zweihänder, but Flynn grabbed the flat sides with both hands and then twisted the blade out of her grip. Before she could react, Flynn impaled the blade through her stomach before kicking her away. In an almost berserk rage, Isabela launched a barrage of punches, all them Flynn dodged. He then grabbed her fists and delivered a powerful uppercut to the chin with his knee, sending blood flying out of her mouth. Next, Flynn threw Isabela in the path of Yubelluna's fireballs, using her as a living shield. Karlamine didn't even have a chance before Flynn came at her with a jump, tackling her to the ground. Putting a knee to her chest, Flynn delivered several punches to her face before she was rendered unconscious.

Pulling out his rocket launcher, Flynn put it into Lock-On Mode and targeted Mihae, launching a barrage of rockets. The girl didn't even have time to flee as she was struck by the projectiles, consuming her in an explosion. Somehow, she managed to survive, as her burnt body was seen falling from the sky. Her body faded into light particles before she hit the ground. _"Lord Riser Phenex's two Rooks, two Knights and one Bishop retired."_

He then focused on Yubelluna, firing again. The Queen was able to conjure a barrier between herself and the oncoming projectiles, and somehow the barrier blocked the explosions. Ravel had also positioned herself behind Yubelluna, throwing fireballs at Flynn who dodged them with ease. The Phenex daughter could tell they would not win this one. Turning to check on her brother, Ravel saw that Riser was also being overwhelmed by his opponent. Said person was no longer in his Balance Breaker, but had poured holy water on Riser's face, greatly burning him. It took quick thinking for Ravel to make her decision. Flying closer towards Yubelluna, she whispered her plan. Yubelluna nodded and Ravel reached into her dress, pulling out a vial containing red liquid and flew towards Riser.

The third Phenex son had just received a brutal blow to the stomach from Issei's gauntlet covered fist, amplified by the cross he was holding when Ravel arrived. The young Phenex threw a fireball at Issei, forcing the Pawn back. Ravel landed beside her brother and gave him the Phoenix Tear. _'Brother is the key here. We need big brother to be in top shape if we're to beat that…that monster!'_ Thought Ravel as Riser drank to liquid.

It was at that moment Grayfia announced. _"Lord Riser Phenex's Queen Retired."_ Unable to withstand the barrage of rockets any longer, Yubelluna was promptly consumed in a powerful explosion. Ravel didn't even have time to register the announcement as her own body was filled with bullet holes. Though she had regeneration, hers was weaker than Riser's, and the pain was too much to endure. She promptly vanished into light. _"Lord Riser Phenex's 1 Bishop retired."_

That just left a recovered Riser, an exhausted Issei and completely fine Flynn. The latter had put away his chaingun and swapped out for his combat shotgun, the grenade launcher mod already attached. The Doom Slayer looked at Issei, winded and wounded and clearly struggling, tried to stand up. "Head back, pervert. You can't beat him in your current state." Flynn said.

Issei glared at the third year. "S-shut up! I can still fight. So what if he's back to full health? I'll beat him down as many times as I-"

Instead of waiting for Issei to continue, Flynn struck him with the butt of his shotgun, knocking the pervert out and retiring him, much to the shock of everyone. "That wasn't a suggestion." Flynn said sternly.

Riser frowned but regained his cocky attitude. "Hmph, I'll admit, defeating my cute servants is impressive. But don't think it will be that simple with me! I'm a Phenex, and I've mastered my-"

Flynn once again cut someone off. This time firing a grenade right into Riser's open mouth. There was a brief moment, and then Riser's eyes and cheeks bulged comically before his head exploded. "Seriously, you people talk way too much." Flynn muttered as he charged towards Riser, whose head had regenerated.

 **(Devils)**

The onlookers were in a state of shock and awe. This sole human had single-handily wiped out an entire peerage of experienced servants while suffering no damage to himself. He didn't even look like he was trying. That caused everyone to start murmuring among each other. Some were wondering who this human was, where he came from, if he came from a line of Magicians, wielded a Sacred Gear or was perhaps a descendant of some hero? There were even a few voicing interests in adding him to their peerages.

The last part made Tiamat scoff. Still standing beside Kuroka, the Nekoshou's eyes were glued to the screen, now showing Flynn facing off against Riser. The idea of turning Flynn into a Devil was stupid as it was suicidal. There was no way Flynn could be turned into a Devil, not with his unique physiology. And if it was possible, he would never allow it, no doubt willing to kill any Devils who tried. Her eyes shifted from the screen towards Sirzechs. The Crimson Devil was approaching her, his maid/wife right behind him. "Lucifer."

"Lady Tiamat." Sirzechs greeted respectfully. He had left his sister when she and the rest of her peerage went to Issei's side after he was rather abruptly retired by Flynn. "I admit, I was a bit surprised when I saw you turning up here with that human…Flynn was it? Ajuka had been curious where his referee had gone."

"I'll apologize to Lord Ajuka. However, Lord Flynn is my Master now and I am honored-bound to serve him." Tiamat said cordially.

Sirzechs' eyes widened a bit. "He made you his familiar? He must be very powerful if he was able to do that."

"You have no idea." Tiamat said. "In fact, what he's showing now can't even be considered the tip of the iceberg. I would prepare to console the Phenex Family in the event Master accidentally kills their son." Her last sentence had Sirzechs frowning. True the human was indeed strong, but surely, he wouldn't be able to do something as kill a Phenex? Still, there was that strange feeling he got from Flynn's presence.

 **(Arena)**

Flynn dodged another fireball coming towards him, responding by firing several rockets at Riser. The Phenex managed to dodge a few but lost two limbs from the rest. Keeping to the air, Riser conjured a spear of flame and threw it at Flynn. But the Doom Slayer merely smacked it to the side and fired another rocket, this one blowing a hole in the Phenex's stomach.

 **[His regeneration is quite impressive]** VEGA noted as Riser's wound began to heal rapidly. **[A repeated barrage of attacks will be necessary to defeat him. Recommend bringing him in for close quarter combat]**

"My favorite type of combat." Flynn said as he brought out a long chain with a pointed tip. Runes could be seen inscribed on the metal as Flynn began to spin it up for momentum. Before Riser could react, Flynn launched the chain right at him, the spear tip piercing Riser's left shoulder. The Phenex would've pulled it out if he wasn't crying out in pain.

"AGH! What is this?!" Roared Riser as he gripped the chain. He winced when his hand began to steam. "What?! Are these holy sigils?!" His words caused the onlooking Devils to gasp in fright. Flynn didn't answer, instead he roughly pulled on the chain, forcing Riser to crash into the ground hard. Next Flynn jumped on top of Riser and began launching a barrage of punches into the Phenex's face.

Riser tried to get up, but Flynn had him firmly pinned with his knee in the Phenex's stomach. And he was beginning to lose conscious. The mere thought that he would lose to a human of all people infuriated Riser that in a last ditched effort, he engulfed his entire body in flames. The sudden burst created a small explosion that consumed Flynn too. Kuroka gasped when she saw this, but Tiamat remained calm.

Smirking, Riser believed that he had killed the human. But that smirk disappeared when a hand grabbed him by the throat. As the smoke cleared, it revealed a still alive Flynn. His jacket and shirt were partially destroyed, revealing the scars and runes that covered his body, including his mark over his heart. Only a few people noticed it.

 **(Grigori)**

Azazel did a spit take when he spotted the mark. Vali, who was entranced by the prowess that Flynn displayed, looked at his leader/guardian in surprised. "Azazel?"

Azazel ignored the drink that had stained his clothes. Instead he paused the image, rewind a little, paused again and then zoomed towards the mark on Flynn's chest. "W-where the hell did that kid get _that_ mark? And those runes? Those are Argent Runes! But the only one…" Azazel began murmuring to himself as he suddenly left. He had to call the other Grigori leaders for a meeting pronto. If this Flynn Blazkowicz was who he thought he was, then things had just gotten serious, nay dire.

Vali remained in his seat. Confused by Azazel's reaction. The White Dragon Emperor had become interested when he watched Flynn defeat all of Riser's servants with ease and then began to deliver a beatdown to the Phenex himself. Still, he was also curious as to what those runes meant. "Albion, do you know anything?" Vali asked the Dragon that dwelled inside of him.

" **Not really, but I feel like I should."** Albion said. **"I can say one thing for certain, those runes are old. Very old. And just by looking at them I can tell that they and that mark hold great power."**

"Power, huh…" Vali mused. A smile formed on his face as he began to see why Ophis had taken such an interest in this human.

 **(Heaven)**

"B-Brother! That mark!" Gabriel stuttered. Her face was of someone who looked like they were seeing a ghost.

She was not the only one. The moment that mark came into view all four Great Seraphs were in a state of shock. For they all knew what that mark was, what it represented and who carried it.

"How can this be?! That person was imprisoned in hell millions of years ago!" Raphael exclaimed.

"Then how do you explain the mark? And those Runes?" Uriel demanded. He had momentarily caused his wings to ignite in holy flames from being surprised. "Not to mention that mark, which can only belong to the one blessed by Azrael!"

"It has to be some kind of trick. There's just no way…" Raphael tried to make an excuse but was cut off by Michael.

"Enough!" The Archangel yelled, silencing the others. Like them he was also in shock at this, but right now they could afford to be scurrying wildly. "We will continue watching the match. Afterwards we will discuss this properly and see where to proceed from there." He added.

The others seemed to still be a bit shaken but nodded. Uriel however commented. "Well, it doesn't look like the match is going to last much longer."

 **(With** **Flynn)**

Flynn was pissed. That had been one of his favorite jackets that he wore even before he got his memories back. And now this chicken torched it! With a roar he delivered a powerful kick to Riser's chin. The impact dislodged Riser's lower jaw and knocked most of his teeth out, in addition of sending him flying. However, with the chain still impaled through his shoulder, he did not get far as he stopped with a sudden jolt.

Gripping the chain on his end, Flynn tugged on it hard. The result was Riser flying back towards him. When he was close enough, Flynn delivered a devastating punch to Riser's face. The strength of the punch not only blew off Riser's face but created a shockwave that shook the arena. Blood flew everywhere and stained the entire ground behind Riser. Without a care Flynn allowed the body to drop to the floor. The Doom Slayer watched impassively as Riser's head regenerated, but it was slow. Slow enough you could see the bones of his skull before being covered by flesh.

Riser was finished, more than that, he was defeated, utterly humiliated, and beaten. Looking up, he weakly saw Flynn's brown eyes glaring down at him, glowing almost ominously. The human than put his foot on top of Riser's head, ready to crush it. No longer wanting to experience any more pain, Riser said two words before losing consciousness.

"I…I forfeit."

 **Chapter is done! Hoped you all liked that. And sorry it took so long. I've been busy with a lot of things, from finishing college to applying for jobs, it has been a crazy few weeks. Please leave a review!**

 **Regarding the recent revelation about the Betrayer (which also puts my entire perspective of reality into question by the way), I managed to think of a way to alter my story with this new information without making any big changes.**


	9. After Beatdown

**I apologize that this took so long. I just got news that my Uncle passed away. It wasn't from the virus, though, not that it matters anyway. We're all still shaken up. Anyway, I am glad you all enjoyed the last chapter. Plus, background on Azrael who was mentioned in the last chapter.**

 **Also, someone asked how the Doom Slayer would be ranked against the stronger members of the DxD Universe. After fighting for eons, his blessings and so forth, Doom Slayer's powers surpassed the strongest beings of the DxD world that he can match or overpower the likes of Melvazoa and Regalzeva.**

 _"Never show hesitation, never show weakness, never show compassion, never show mercy, never show remorse. For you shall be shown none."_

 _Corrax Entry 1:5_

 **(Earth, Eons Ago)**

A young six-year-old Flynn was staring at a painting in his father's personal office. The office was of a suitable size, with a desk and chair, a window at the back. There were some shelves filled with items, trophies, weapons and more objects. There were other portraits hanging on the walls. Some were of family members, Flynn's father in his Sentinel Armor, both his parents and all three them. There was even one with Flynn and Daisy when he first got the rabbit. But it was this portrait specifically that had gotten the boy's attention. The image was that of a purple serpent dragon with grey eyes in space, with dozens of small white stars in the background. The interesting part was that the dragon was biting its own tail, forming a circle in the process. Below it was a word that Flynn was trying to spell out.

"O…Our…Ouro…Ouroboros! Ouroboros!" Flynn cheered as he managed to say the word.

"Flynn?"

Jumping, Flynn Blazkowicz spun around. Walking inside was his father, William Joseph Blakowicz III. He was wearing regular clothes, his Sentinel Armor levitating in a protective force-field to the right of the office. The black-haired man had a small frown on his face. "Flynn, what did I tell you about coming in here?" He asked sternly, his blue eyes looking at Flynn.

Flynn shuffled his feet. "Don't…" He mumbled, feeling ashamed.

Seeing his son's expression, William's softened. Placing a hand on Flynn's head, the older Blazkowicz ruffled his hair. "Just remember next time. There's some stuff here that could hurt you. I don't want that, okay?"

Flynn nodded, relieve that his father wasn't angry. "I'm sorry, but I wanted to see this picture. What is it daddy?" He asked, pointing at said portrait.

William followed his son's finger towards the painting. His eyes widened a bit before a smile formed in understanding. "Not 'what', son. 'Who' is the correct term." William said as he took the painting down so Flynn could see it better. "It's called the Ouroboros, or the Infinite Dragon. It is said to represent the infinite cycle of life and death, destruction and creation. In fact, your mother would liken it to the Elemental Wraiths."

"Really?" Flynn asked, remembering the stories his Argenta mother, Victoria Bethian, would tell him about the gods of the Argenta. The ones whom her clan still worshipped despite the coming of the Maykrs.

"Yep, for us humans, it and the Aeons were seen as the protectors of Earth and mankind after the apocalypse nearly destroyed us, long before the Night Sentinels came."

"Wow~" Flynn said in awe and looked back at the painting. He wondered if he could ever meet them.

 **(Present Time, With Flynn)**

Flynn was nowhere near done with this asshole. Forfeit? Wasn't this imp trying to kill him? Did he not think that he wouldn't be killed in turn? The Doom Slayer found himself slowly being taken over by rage as he grabbed Riser by the throat. Flynn fully intended to rip out the Devil's head, and perhaps most of his spine, from his body when he suddenly found himself warped back into the Reception Hall. Once more he was surrounded by gobsmacked Devils while still holding onto an unconscious Riser's head.

"Flynn Blazkowicz. You are the victor." Sirzechs said as he approached the human. "As such, you are free to have Black Cat and all charges against her shall be dropped. In addition, since Hyoudou also assisted in Riser's defeat, the engagement between Riser and Rias has been cancelled."

Internally, Sirzechs let out a sigh of relief as Riser forfeited the match. At last his sister was freed of this engagement and could now live her life freely. And apparently said life would be with her Pawn if the look of adoration from her was of any evidence.

To be honest, his original plan was to have the Red Dragon Emperor defeat the Phenex, but this was also good. True, there would be a new investigation regarding the Black Cat, Kuroka. But, to study the capabilities of this young man, Flynn Blazkowicz. His feelings on what he saw were mixed. While he was pleased that Blazkowicz defeated Riser, it showed just how powerful the human was. He was strong…too strong. He mowed down the peerage with ease and in a short amount of time and didn't even break a sweat, and then crushed Riser even after the Phenex was rejuvenated thanks to the Phoenix Tears. And yet, a voice in the back of his head told Sirzechs was that this wasn't even a fraction of Blazkowicz' true power. That thought alone made Sirzechs nervous. Right now, though his concern was getting Flynn to let go of Riser.

"Now, if you could release Riser…" Sirzechs said, but was cut off by a glare from Flynn.

"And why would I do that?" He asked nonchalantly. His grip on Riser's throat tightened, enough to make the Phenex let out a gurgle noise. "If I recall, he attempted to kill me, so isn't it only necessary to return the favor?"

Sirzechs frowned. He could see that Flynn was dead serious on killing Riser, damn the repercussions. "Be that as it may, I must ask you let him go. If not, I will have to use force."

Flynn raised an eyebrow. There was a tense moment of silence as everyone waited to see what would happen. None of them breathed as the two stared down one another. Surely the human wouldn't try and stand against the Lucifer, would he? Before they could even blink, Flynn disappeared at a speed none of the Devils had even seen before. One moment he was about to break Riser's neck, the next he shoved his fist deep into Sirzechs' stomach. The force of impact caused the Red Satan to let out a gasp of pain and skid back several feet. Many Devils gasped at this display of strength and speed.

However, Flynn titled his head, and then smirked. "Hmph, show off." He muttered under his breath. The Doom Slayer spared the unconscious form of Riser Phenex a small glance. The blonde young man was already being tended too. Even if Flynn didn't kill him, the Devil's psyche was no doubt thoroughly broken. And sometimes, a scared demon was better than a dead one, especially for one's amusement. "Fine, this place was already starting to smell anyway. Tiamat, grab Kuroka and let's go."

Tiamat nodded and helped Kuroka to her feet. The Nekoshou immediately launched herself to Flynn, who was forced to catch her bridal style. He ignored Kuroka nuzzling into his neck as Tiamat activated her magic circle and the three of them vanished. The entire hall was then filled with dozens of relieved sighs, something all the Devils had been holding in.

There were a few exceptions. At the corner of the room, Mephisto smirked. He had been excited as he watched Flynn beat down Riser. Followed by landing a strong blow to Sirzechs' stomach. Oh, the Red Satan might've put up a strong front. But anyone with good eyes and ears could tell that the Doom Slayer had done a lot more damage than just breaking a few ribs. The Devil was doing a good job of not showing how much pain he was in.

"Mephisto!" A voice hissed, getting said Demon's attention.

Turning to his right, he saw Zekram Bael march up to him. The first Bael Head had an expression that was a mix of anger and fear. He got a few glances, but no one dare speak as they decided to focus on other matters.

"Lord Zekram. What seems to be the matter?" Mephisto asked innocently.

"Drop the act Mephisto! You know why." Zekram said as he pointed a finger. "I saw how he fought! I saw that mark on his chest! It's _him_ isn't it?! How the hell did you bring him here?!"

Mephisto shrugged. "I will neither deny nor acknowledge if it's the Doom Slayer or not. It would ruin the fun."

Zekram scowled. "You think this is funny?" He asked. "It is only a matter of time until he continues what he started. Starting with us." Zekram finished before walking away. He needed to speak with the Four Satans and fast before it was too late. Mephisto meanwhile just continued smiling.

 **(Flynn's** **House)**

The trio reappeared in Flynn's living room. The Doom Slayer put Kuroka down as he stretched his arms. "Now that's done with it. Kuroka, next time be more-MMPH!"

Flynn was cut off when Kuroka suddenly latched her lips on his. It was so sudden that for the first time in his life, Flynn was stunned and confused. After a few seconds, Kuroka slowly broke the kiss, removing her hands from Flynn's cheeks. She was painting heavily while Flynn was okay, her cheeks pink and his eyes wide.

"That was my first kiss nya~" Kuroka said before walking off. There was a seductive sway in her hips that Flynn paid attention to. Tiamat, who was also surprised, looked at Flynn and noticed he was strangely quiet. "Master?"

Flynn was quiet. "I need to go for a drive." He muttered as he told Tiamat to relax and that everything was fine.

Next, Flynn was riding He wasn't blind, it was clear that Kuroka was infatuated with him to some degree if she was willing to do that. The problem was he had no idea how to respond. Flynn wouldn't lie and said Kuroka was attractive, even a blind man could see that. However, after fighting and killing for eons, focusing on nothing but the eradication of demons, Flynn had never really focused on other things like love. There was one time he held such feelings, but that was before he lost everything. Since that time, he had buried such emotions, along with compassion, joy and pity.

To be honest, this whole new experience was something he had not fully adjusted too. Not fighting every single moment, going to school, just hanging out at the house. This was all still new for him, or rather what he once had but left behind. And then there was Tiamat. While Flynn was happy to have found the little hatchling he had raised, he wasn't sure if Tiamat should come with him when Flynn eventually begins his crusade against the slaves of Doom again. No matter how much she grew, she was still the little dragon he remembered. Then there were the Maykrs…

 **[-Slayer! Doom Slayer!]**

Flynn's thoughts were broken by VEGA. Stopping his motorcycle, the Slayer realized that he was not in Kuoh anymore. Rather he was on the outskirts of the town, surrounded by trees, grass and rocks. Not a living person in sight.

"VEGA, what the hell is going on?!" Flynn shouted as he got off his bike, immediately pulling out his combat shotgun.

 **[I do not know. One moment you were driving normally, the next I felt a foreign energy take over your mind, casting illusions perhaps. I had tried to awaken you, but the force was strong]** VEGA answered. **[Only a powerful entity could cast illusions on someone like you. Please be cautious]**

Flynn nodded as he scanned his surroundings. He saw nothing but could feel something close. Something strong, very strong. At first Flynn figured those Devils were attempting an assassination or something

"…Hello"

Eyes widening at the sudden voice from behind, Flynn spun around. At the same time, the Praetor Suit suddenly materialized over his body. **[It appears the Praetor Suit has appeared. It must have reacted to the current situation. Interesting]** VEGA noted as he checked the armor's systems.

The Doom Slayer was not listening to VEGA. Instead his focus was on the being in front of him. Despite having the appearance of a young girl, the creature could not be human. Flynn could feel the power rolling off her. Yet he stood his ground, he had faced powerful entities before, some not even demons, and prevailed. If a battle came down to it, then this would be no different.

Ophis spoke once more. "I've, been waiting to speak with you…Doom Slayer." She said. Though her voice had no emotions, you could feel the excitement. Plus, the small smile on her face.

"You are…the Ouroboros." Flynn said. He relaxed a bit but remained vigilant in case she attacked.

"I am. And I want you to join me." Ophis said.

"Isn't that why you sent Kuroka?" Flynn questioned. He never really did ask what the Ouroboros' plan was.

"I can no longer wait. For a long time, I have tried to regain my home, my silence. But the pest who inhabits it now cannot be easily beaten. Thus, I require the strength of others." She then looked straight into Flynn's eyes, even if they were covered by his helmet's visor. "You're here now, though. One who once worshipped me. One imbued with the eldritch, the divine and the demonic powers. An entity unique, even to me. I know of your strength. You can help me take back my home."

 **[From what I understand, the Ouroboros resides in the Dimensional Gap, the space between all worlds and even universes]** VEGA commented. **[It's one of the reasons why the demons require things such as gore nests and Hell Portals to invade worlds]**

"Now, join me." Ophis continued her speech. She was not just a few inches from Flynn, standing before him without an ounce of fear. She raised a hand. "Help me remove the pest, and I shall grant you what you desire most."

 **(Next Day, Gremory Mansion)**

Serafall and Ajuka were walking down the familiar hallways of the Gremory Mansion. The duo along with Falbium Asmodeus had received an unexpected summon from Zekram Bael to meet with Sirzechs at his family's home. While he did not have the authority to command the Satans, Zekram's influence over their society was equal if not greater than theirs, thus gave them some control over them. However, it was rare for Zekram to request anything from them and from the sound of his voice, it was something important.

The butler that was escorting them opened the door to one of the mansion's many living rooms. Along with the fancy furniture, portraits and other accessories, Falbium was also present, but was surprisingly awake. Sirzechs meanwhile was sitting on another couch, Grayfia dutifully by his side. What caught Serafall and Ajuka's attention were the bandages around Sirzechs chest, revealed by his uniform being opened. Sirzechs also seemed a bit pale too, as if he had just released a large amount of his contents.

"Ah you're here." Sirzechs said, speaking normally.

"Sirzechs…What the hell happened to you?" Ajuka asked. He couldn't even remember the last time he saw his best friend in such a state. Not since the Civil War had Sirzechs been this badly injured.

Sirzechs smiled weakly, coughing a little. "I'm afraid this is the result of getting punched in the stomach." He winced as his wife proceeded to wrap a fresh set of bandages. "All my ribs have been broken, my left lung was pierced and it's hard to eat a little."

It took a moment, but Ajuka realized who Sirzechs was talking about. "The human? The one who defeated the Phenex boy? He did this with one punch?" The Beelzebub found it hard to believe. Humans were the weakest of the races. Though there were few exceptions, Ajuka could only think of Vasco Strade back in his prime who could injure a Super Devil like Sirzechs.

"I know what you're thinking." Sirzechs said, looking at the green haired Devil. "Flynn Blazkowicz is a rare type of human obviously. He used no Sacred Gear nor magic that I could detect, not even Senjutsu. It was pure strength…or maybe something else. The important part was that I even instinctively covered myself with my aura and not even that fully protected me. In fact, you could say it's what saved my life."

"You used your Power of Destruction and still ended up like this?!" Serafall exclaimed. The sole female Satan had already sat down, munching on some sweets.

Their conversation ended when the same butler opened the door. "Apologies, Satans. But Lord Zekram has arrived." The man said.

"Let him in." Nodded Sirzechs.

The butler bowed and closed the door. Seconds later Zekram came in. Under his arm were several stone tablets that had the same green glowing symbols on them. The tablets were old, very old going by their appearance. Yet the magic they radiated was still strong enough for the Satans to sense them.

"I thank you for all coming here." Zekram said in an even tone, still sounding polite. "Before we begin, I must ask your Queen to leave, Lucifer. This is something only meant for the Satans." He finished as he looked at Grayfia.

Sirzechs frowned. What could be so important that he didn't even trust his own wife/Queen to be here to listen? Nevertheless, it was clear that Zekram was serious. Sirzechs gave a nod to Grayfia, indicating she could leave. The maid seemed unsure, but she trusted her husband, thus complied as she walked out of the room. Once she closed the door, Zekram cast several spells that would ensure that no one could hear what was being said. The Satans noted that these were high-level spells, meaning this must've been serious.

Finally sitting down, Zekram looked at the four. "The reason I have called you here is a matter of the upmost importance…and the possible survival of our race."

"Does this have to do with that human boy?" Falbium asked, fully awake for once.

" _That_ is no boy." Zekram snarled, surprising the younger Devils with the level of malice in his tone. "But he is human. First off, what do you know of our people's history?"

Ajuka blinked. "Only what has been taught. That Hell was becoming barren, resources running dry and falling apart. The original Satans moved the survivors to the Underworld, where we became the Devils."

"That's just the cover story." Zekram revealed. "To hide the truth and solidify their power hold. We, the original heads of the 72 Pillars, the Four Original Satans, those who became the Extra Demons, were running. We had given our support to Lucifer to rule Hell, but his coup failed and to escape from Satan's wrath we came here to the Underworld. Escape from him… and from a being who nearly brought upon us our extinction."

As he finished speaking, Zekram had set up the tablets on the coffee table. Each one had the same green glowing symbol on them. And for some reason the younger Devils felt a chill go up on their backs just from looking at it. One by one, Zekram gently pressed each symbol. As he did, a deep demonic voice began to speak.

" **In the first age, in the first battle, when the shadows first lengthened, one stood. Burned by the embers of Armageddon, his soul blistered by the fires of Hell and tainted beyond ascension, he chose the path of perpetual torment. In his ravenous hatred he found no peace; and with boiling blood he scoured the Umbral Plains seeking vengeance against the dark lords who had wronged him. He wore the crown of the Night Sentinels, and those that tasted the bite of his sword named him... the Doom Slayer."**

" **Tempered by the fires of Hell, his iron will remained steadfast through the passage that preys upon the weak. For he alone was the Hell Walker, the Unchained Predator, who sought retribution in all quarters, dark and light, fire and ice, in the beginning and the end, and he hunted the slaves of Doom with barbarous cruelty; for he passed through the divide as none but demon had before."**

" **And in his conquest against the blackened souls of the doomed, his prowess was shown. In his crusade, the Seraphim bestowed upon him terrible power and speed, and with his might he crushed the obsidian pillars of the Blood Temples. He set forth without pity upon the beasts of the nine circles. Unbreakable, incorruptible, unyielding, the Doom Slayer sought to end the dominion of the dark realm."**

" **The age of his reckoning was uncounted. The scribes carved his name deep in the tablets of Hell across eons, and each battle etched terror in the hearts of the demons. They knew he would come, as he always had, as he always will, to feast on the blood of the wicked. For he alone could draw strength from his fallen foes, and ever his power grew, swift and unrelenting."**

" **None could stand before the horde but the Doom Slayer. Despair spread before him like a plague, striking fear into the shadow-dwellers, driving them to deeper and darker pits. But from the depths of the abyss rose The Great One, a champion mightier than all who had come before. The Titan, of immeasurable power and ferocity. He strode upon the plain and faced the Doom Slayer, and a mighty battle was fought on the desolate plains. The Titan fought with the fury of the countless that had fallen at the Doom Slayer's hand, but there fell the Titan, and in his defeat the shadow horde were routed."**

" **And in his terrible rancor between worlds and through time, the Hell Walker found the wretch who shall not be named, but in his heresy was loyal to his evil cause. The wretch adorned the Doom Slayer in a mighty armor, wrought in the forges of Hell, impenetrable and unyielding. With sword and shield of adamantine strength, the Doom Slayer set to banishing all that were left unbroken by his savagery to the void."**

" **Yet as the mighty Titan fell and dread engulfed the armies of Doom, the demon priests of the Blood Temples laid a trap to capture this scourge of Hell. Insatiable, even by the vanquishing of the Great One, the Hell Walker sought prey in the tombs of the Blood Keep. And blinded by his fervor, the lure drew him in. The priests brought down the temple upon the Doom Slayer, and in his defeat entombed him in the cursed sarcophagus. The mark of the Doom Slayer was burned upon his crypt, a warning to all of Hell that the terror within must never be freed. There he lies still, and ever more, in silent suffering."**

Silence reigned in as the last tome finished. All of four Satans had their eyes glued to the tomes, as if expecting that voice to speak again. Zekram had his arms crossed, a stern frown on his face. Sirzechs swallowed, the sheer intensity of the voice and how it spoke the story was enough to make him nervous.

"Such a being…did he truly exist?" Ajuka asked, the first to finally speak.

"I saw him once. Back when I was young." Zekram said. The memories of the invasion of Argent D'Nur surfacing after so many years. "I led an army of a thousand demons, many of whom were Ultimate and Satan-class. None of them stood a chance as the Slayer slaughtered them with his bare hands." He looked at the two Super Devils in the room. "Even if you worked together, unleashed your 'true' forms, you would be naught but more lives to add to his tally. We couldn't even kill him for fear of his soul returning to torment us more."

"And this Flynn Blazkowicz…you think he could be him?" Serafall asked, no longer cheerful but now serious.

"I saw his body he had his mark on his chest." Zekram replied. "I don't know how he escaped or ended up here, but its only a matter of time until he decides to continue what he started." He then looked directly at Sirzechs and Serafall. "We need to keep an eye on him, which is why I want your sisters and their peerages to keep watch over Blazkowicz."

"What?!" Sirzechs cried, with Serafall also having a look of outrage. He shot up but immediately sat down, wincing as his wound pulsed. Ajuka helped his friend get comfortable. "If what you say is true then we need to evacuate them immediately. As their siblings it's our job-"

"YOUR JOB IS TO PROTECT THE UNDERWORLD!" Zekram shouted, startling the younger Devils. "To protect our kind! That is why you took the position of Satans. The Doom Slayer is the greatest threat to our people in our entire history, even more than the other factions. Do not let your personal feelings get in the way of your duty. We must be prepared should he finally decide to make his move. If you cannot…then I will have to push for you to resign from your posts."

The Satans were silent. While they were technically the leaders of the Devils, it was Zekram Bael who held the strongest political influence among their kind. In fact, it would be best to say that the Great King was the true ruler of the Underworld, ever since the original Satans died in the war. His threat was not just hollow words, but a fact. Zekram could easily strip them of their rank or limit their power. They knew he would never do anything drastic but could still do something the Satans would regret. So, with a heavy heart, Serafall and Sirzechs had no choice but to reign into his demands.

 **(Unknown Location)**

"Azazel…"

"…Michael"

Azazel and Michael, leaders of the Grigori and Heaven respectively, were meeting in a restaurant owned by the former. VIP section so they could talk in private. Despite being on opposing sides, there was still a sense of camaraderie, familial ties, that they could communicate with one another friendly. Both were wearing their normal attires, though Azazel's suit was more casual and normal than Michael's robes and armor.

"When you asked to speak with me, a lot of my boys were a bit nervous. I told them that it was okay, though. You're not the type to put down traps." Azazel said with a small smile. It disappeared when Michael didn't return it with one of his signature smiles. "I'm guessing you saw the broadcast from yesterday."

"The ones the Devils showed. Yes." Michael responded. "Do you know anything about who requested it to be aired publicly?"

"From what I managed to learn it was Mephisto." Azazel said as he took a drink of beer. "Excluding the fact that the man hasn't been involved with Devil politics since the war, his presence confirms my own theories. I'm guessing you had the same as me."

Michael nodded. "The Doom Slayer. That boy, Flynn Blazkowicz, is him. I already looked at the Book of Souls, and his name could not be found. The mark on his body also proves his identity."

"Azrael's chosen." Mused Azazel. The two angels had a faraway look as they recalled their brother. "Heh, I can never forget that guy. His personality did not fit his appearance or title as Angel of Death at all."

"There was no one more compassionate or loyal as him." Michael said in agreement. "His disappearance was a great loss to Heaven. Even Father mourned him. Sometimes I wonder how things would be if he was still here with us."

"Out of all of us, he was the one who took Helel's betrayal the hardest. And what he did to Earth." Azazel added. "But that never stopped him from ensuring that the souls of the deceased made their way safely to Heaven. Perhaps that's why he helped the Doom Slayer."

"Back to the Slayer, how do you suppose the Devils will react?" Michael asked.

Azazel shrugged. "Their leaders made sure any knowledge of him was sealed off. The only one who would probably recognize him would be Zekram. He will probably tell the Satans but won't do anything drastic. The old guy knows that with their current situation they cannot do anything that will risk their safety. Now for the Old Satan Faction…"

"They might try doing something dangerous." Michael finished. "Heaven is not like what it once was. We do not have the strength to face them as we could in the past. Not after what happened with Argent D'Nur, the Wraiths and Urdak."

"You still can't get through the Maykrs?" Azazel asked.

The Archangel shook his head. "We have been completely cut off from them. The only evidence we have that they have not turned on us is because the system remains active, so they must be gathering believers from across the stars. Other than that, I do not know what the Khan Maykr is doing."

"Hmm." Azazel hummed. "Well, nothing we can do about them, Maykrs or demons. Might as well focus on the Doom Slayer. What is Heaven's plan?"

"For now? Nothing." Michael answered. "We do not have the manpower to observe him and guard our borders at the same time. But we shall try to keep our ears open. What about you, brother?"

"Eh, not sure yet. I got wind that he killed a small team of mine because they decided to go rogue. Might be risky to get in contact with him." Azazel explained. "However, Tobio told me the Doom Slayer rescued Lavinia. I might try sending his team since its less likely he'll kill them."

"I see" Michael said. "I know this may sound strange, but please keep me inform of any new developments regarding Flynn Blazkowicz."

Azazel shrugged. He saw no problem with that. "Sure, so long as you do the same. Now let's order something. This restaurant makes some damn good pasta!"

 **(Same time, Kyoto)**

A magic portal appeared in front of Yasaka's home. Seconds later Flynn came riding out on his motorcycle, wearing his casual clothes, a sage shirt, black jeans, leather jacket and black boots. He parked the bike near the gate, taking his helmet off and placed it on one of the bike's handlebars and then using Argenta runes to ensure the bike could not be stolen. **[I was not aware you could use your people's runes]** VEGA said.

" _How else do you think I could use all those runes I picked up when on Mars and in Hell?"_ Flynn asked rhetorically. He showed his identity to the guards as they let him enter the grounds. _"My mother taught me them, and I learned more about them back on Argent D'Nur. Never saw much use for them except for support to be honest. Still, never hurts."_

 **[Back to yesterday, are you sure it was wise to reject the Ouroboros' offer?]** VEGA asked. **[Surely it could've helped you eliminate the demons]**

" _Whether it could or could not is up for debate. And there's no telling if it would keep its end of the bargain."_ Answered Flynn. Besides…wiping out the demons wasn't his only desire. _"Though it was strange that it left after that. It could've taken me by force."_

 **[You give it to much credit, Doom Slayer. Though a powerful entity, I calculated that you had a 50% chance of victory. Despite that, the resulting conflict would've resulted in massive collateral damage and no doubt drag in humans. I can only assume it will return later to make the same offer again]**

" _We'll see."_ Was all Flynn said. He was just about to knock on the door when a golden blur to slam into him. The impact would've knocked down anyone else, but for Flynn, he merely staggered a bit before holding said blur. It was none other than Kunou who was clutching Flynn's shirt.

"Hey Kunou, been good?" Flynn asked as Kunou continued to hug Flynn.

"Yeah! Kaa-san and I watched you beat up that stupid Devil! You were so cool!" Kunou cheered, earning a smirk from Flynn. The young Kyuubi took her position on Flynn's shoulders as the Doom Slayer entered. In the living room, sitting at a table was Yasaka. VEGA had materialized a drone body and was hovering beside Flynn.

"Hello Flynn-san. I'm glad that you're doing okay. I was worried that you might still be recovering from your battle." Yasaka said politely.

"I wasn't even hurt." Flynn said as he sat down opposite of Yasaka. Kunou had gotten off his shoulder and had gone over to some markers and papers that were on the floor nearby. While she was doing her own thing, Flynn kept speaking. "Were you two the only ones watching the match?"

"No, there were a few others. A lot of Youkai were quite please to see you demolish that Devil so quick and easily." Yasaka replied. She recalled how many of her people cheered Flynn took down each of Riser's servants, following the beatdown the Phenex scion himself faced. "If you don't mind, what exactly is your relationship with the Black Cat, Kuroka? And the Chaos Karma Dragon for that matter." The older Kyuubi asked, subconsciously leaning forward a bit.

A bit confused by her question Flynn went on to explain the situation. It took about a good twenty minutes, but by the end Yasaka seemed pleased with what she heard. She seemed most relieved when Flynn said that Tiamat was his familiar and his connection with Kuroka was simply professional. "I see. I had my suspicions about her so called 'madness', but to hear that her former King attempted to force make a Super Devil is quite appalling."

"My only regret is that I didn't get to put the scumbag down myself." Flynn commented. "Anyway, your message said you had a job for me?"

"Ah yes, that." Yasaka said. "In a few hours, delegates from the Norse Pantheon will be arriving soon. I've been asked by the Shinto Leaders to meet with them as their representative and leader of the Kyoto Youkai Faction."

"Norse?" Flynn repeated. He had read about them from the information that Mephisto gave him. "Why would they be coming here?"

"Sometimes factions and pantheons would meet for mutual benefits, or to maintain stability between our sides. It doesn't happen often, but enough that it isn't uncommon either." Yasaka explained. "However, that also makes it a good opportunity for…others to act. People dissatisfied with the status quo, wishing to use this opportunity to cause conflict between factions. Others who want to usurp current leaders and take over. At the moment, there have been strange actions happening near the borders of Kyoto and my forces are currently spread thin. So, that is why I wanted to hire you. Rest assured you will be properly paid."

"Okay."

"Eh?" Yasaka said. "R-really?" She asked, surprised by the quick response Flynn gave.

Flynn shrugged. "Sure, I've been needing some cash and a chance to get away from that Devil town. Besides, I don't mind helping out."

"Great! I'm so happy!" Exclaimed Yasaka, surprising Flynn by her enthusiasm. When she realized this, she calmed down, a small blush on her cheeks. "Your presence will be a great boon for me…for more reasons than one."

"Is the leader of the Norse Faction that much of a problem?" Flynn asked.

Yasaka frown. "Not for reasons you would think. The Allfather Odin is known for his willingness to have peaceful talks with other factions. The problem is that…how can I put this…"

"He's an ero-jisan!" Kunou exclaimed from her spot. She had just finished her drawing of Flynn.

"Kunou!" Yasaka admonished her daughter, but it was clear that Kunou's description was correct as she went on how Odin would do perverted stuff in front of the leader of Kyoto. Flynn frowned as he heard all of this, finding this all rather disturbing. He then looked at Yasaka.

"Want me to castrate him?"

 **Finally finished this chapter! I hoped you all liked this and be sure to leave me a review!**

 **Regarding Flynn's harem, so far, I have Kuroka, Yasaka, Lavinia, Roseweisse and Lint. Those are the best girls I can think of right now.**

 **Again, leave a review and check out my Doom/Warcraft challenge. And regarding other crossovers, I'm thinking of doing one with Doom and Wolfenstein, which is weird since no one has done one yet.**


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